diff --git a/frontend/src/api/monitorApi.ts b/frontend/src/api/monitorApi.ts
index 441ab6d..58d4bf1 100644
--- a/frontend/src/api/monitorApi.ts
+++ b/frontend/src/api/monitorApi.ts
@@ -68,7 +68,7 @@ export const monitorApi = {
     return fetchJson(`/api/monitoring/query-metrics/summary?hours=${hours}`)
   },
 
-  getQueryMetricsTimeSeries(days = 7): Promise<QueryMetricsTimeSeries> {
-    return fetchJson(`/api/monitoring/query-metrics/timeseries?days=${days}`)
+  getQueryMetricsTimeSeries(days = 7, groupBy: 'ip' | 'id' = 'ip'): Promise<QueryMetricsTimeSeries> {
+    return fetchJson(`/api/monitoring/query-metrics/timeseries?days=${days}&groupBy=${groupBy}`)
   },
 }
diff --git a/frontend/src/pages/Dashboard.tsx b/frontend/src/pages/Dashboard.tsx
index b8ca85a..42db6a9 100644
--- a/frontend/src/pages/Dashboard.tsx
+++ b/frontend/src/pages/Dashboard.tsx
@@ -32,6 +32,7 @@ export default function Dashboard() {
   const [running, setRunning] = useCachedState<RunningJob[]>('dash.running', [])
   const [queryTs, setQueryTs] = useCachedState<QueryMetricsTimeSeries | null>('dash.queryTs', null)
   const [days, setDays] = useState(7)
+  const [clientGroupBy, setClientGroupBy] = useState<'ip' | 'id'>('ip')
   const [isQueryChartsOpen, setIsQueryChartsOpen] = useState(() =>
     localStorage.getItem('dashboard-query-charts') !== 'collapsed',
   )
@@ -51,8 +52,8 @@ export default function Dashboard() {
     monitorApi.getDelay().then(setDelay).catch(() => {})
     batchApi.getDailyStats().then(setDaily).catch(() => {})
     batchApi.getRunningJobs().then(setRunning).catch(() => {})
-    monitorApi.getQueryMetricsTimeSeries(days).then(setQueryTs).catch(() => {})
-  }, POLL_INTERVAL, [days])
+    monitorApi.getQueryMetricsTimeSeries(days, clientGroupBy).then(setQueryTs).catch(() => {})
+  }, POLL_INTERVAL, [days, clientGroupBy])
 
   const memUsage = metrics
     ? Math.round((metrics.memory.used / metrics.memory.max) * 100)
@@ -327,7 +328,21 @@ export default function Dashboard() {
                 {/* Top Clients */}
                 {queryTs.topClients.length > 0 && (
                   <div>
-                    <div className="mb-2 text-sm font-medium text-muted">{t('dashboard.topClients')}</div>
+                    <div className="mb-2 flex items-center gap-2">
+                      <span className="text-sm font-medium text-muted">{t('dashboard.topClients')}</span>
+                      <div className="flex overflow-hidden rounded-md border border-[var(--border-primary)] text-xs">
+                        <button
+                          type="button"
+                          className={`px-2 py-0.5 ${clientGroupBy === 'ip' ? 'bg-[var(--accent-primary)] text-white' : 'text-[var(--text-secondary)]'}`}
+                          onClick={() => setClientGroupBy('ip')}
+                        >IP</button>
+                        <button
+                          type="button"
+                          className={`px-2 py-0.5 ${clientGroupBy === 'id' ? 'bg-[var(--accent-primary)] text-white' : 'text-[var(--text-secondary)]'}`}
+                          onClick={() => setClientGroupBy('id')}
+                        >ID</button>
+                      </div>
+                    </div>
                     <div className="space-y-2">
                       {queryTs.topClients.map((c, i) => {
                         const maxCount = queryTs.topClients[0].query_count
diff --git a/src/main/java/gc/mda/signal_batch/global/config/WebSocketStompConfig.java b/src/main/java/gc/mda/signal_batch/global/config/WebSocketStompConfig.java
index e9f478d..e8f0c46 100644
--- a/src/main/java/gc/mda/signal_batch/global/config/WebSocketStompConfig.java
+++ b/src/main/java/gc/mda/signal_batch/global/config/WebSocketStompConfig.java
@@ -22,8 +22,10 @@ import org.springframework.http.server.ServletServerHttpRequest;
 
 import com.fasterxml.jackson.databind.ObjectMapper;
 
+import jakarta.servlet.http.Cookie;
 import jakarta.servlet.http.HttpServletRequest;
 import java.security.Principal;
+import java.util.Base64;
 import java.util.List;
 import java.util.Map;
 import java.util.UUID;
@@ -180,11 +182,18 @@ public class WebSocketStompConfig implements WebSocketMessageBrokerConfigurer {
             String clientIp = extractClientIp(request);
             attributes.put("CLIENT_IP", clientIp);
 
-            // User-Agent 추출
             if (request instanceof ServletServerHttpRequest) {
                 HttpServletRequest servletRequest = ((ServletServerHttpRequest) request).getServletRequest();
+
+                // User-Agent 추출
                 String userAgent = servletRequest.getHeader("User-Agent");
                 attributes.put("USER_AGENT", userAgent);
+
+                // GC_SESSION 쿠키에서 JWT email 추출 (guide 서비스 인증)
+                String clientId = extractEmailFromJwtCookie(servletRequest);
+                if (clientId != null) {
+                    attributes.put("CLIENT_ID", clientId);
+                }
             }
 
             return true;
@@ -225,5 +234,43 @@ public class WebSocketStompConfig implements WebSocketMessageBrokerConfigurer {
             // ServletServerHttpRequest가 아닌 경우 기본값
             return "unknown";
         }
+
+        /**
+         * GC_SESSION 쿠키에서 JWT payload의 email 클레임 추출.
+         * JWT 검증은 nginx auth_request에서 이미 완료 — 여기서는 payload 디코딩만 수행.
+         */
+        private String extractEmailFromJwtCookie(HttpServletRequest request) {
+            Cookie[] cookies = request.getCookies();
+            if (cookies == null) return null;
+
+            String token = null;
+            for (Cookie cookie : cookies) {
+                if ("GC_SESSION".equals(cookie.getName())) {
+                    token = cookie.getValue();
+                    break;
+                }
+            }
+            if (token == null || token.isEmpty()) return null;
+
+            try {
+                // JWT: header.payload.signature — payload만 Base64URL 디코딩
+                String[] parts = token.split("\\.");
+                if (parts.length < 2) return null;
+
+                String payload = new String(Base64.getUrlDecoder().decode(parts[1]));
+                // 간단한 JSON 파싱 (Jackson 의존 없이): "email":"value" 추출
+                int emailIdx = payload.indexOf("\"email\"");
+                if (emailIdx < 0) return null;
+
+                int colonIdx = payload.indexOf(':', emailIdx);
+                int quoteStart = payload.indexOf('"', colonIdx + 1);
+                int quoteEnd = payload.indexOf('"', quoteStart + 1);
+                if (quoteStart < 0 || quoteEnd < 0) return null;
+
+                return payload.substring(quoteStart + 1, quoteEnd);
+            } catch (Exception e) {
+                return null;
+            }
+        }
     }
 }
\ No newline at end of file
diff --git a/src/main/java/gc/mda/signal_batch/global/websocket/controller/StompTrackController.java b/src/main/java/gc/mda/signal_batch/global/websocket/controller/StompTrackController.java
index 37c9b1b..ff7f869 100644
--- a/src/main/java/gc/mda/signal_batch/global/websocket/controller/StompTrackController.java
+++ b/src/main/java/gc/mda/signal_batch/global/websocket/controller/StompTrackController.java
@@ -71,11 +71,17 @@ public class StompTrackController {
             }
         };
 
-        // 세션 속성에서 CLIENT_IP 추출
+        // 세션 속성에서 CLIENT_IP, CLIENT_ID 추출
         String clientIp = null;
+        String clientId = null;
         Map<String, Object> sessionAttrs = headerAccessor.getSessionAttributes();
-        if (sessionAttrs != null && sessionAttrs.containsKey("CLIENT_IP")) {
-            clientIp = (String) sessionAttrs.get("CLIENT_IP");
+        if (sessionAttrs != null) {
+            if (sessionAttrs.containsKey("CLIENT_IP")) {
+                clientIp = (String) sessionAttrs.get("CLIENT_IP");
+            }
+            if (sessionAttrs.containsKey("CLIENT_ID")) {
+                clientId = (String) sessionAttrs.get("CLIENT_ID");
+            }
         }
 
         // 비동기 스트리밍 시작 - 청크 모드 체크
@@ -86,7 +92,8 @@ public class StompTrackController {
                 sessionId,
                 chunk -> sendChunkedDataToUser(userId, chunk),
                 statusCallback,
-                clientIp
+                clientIp,
+                clientId
             );
         } else {
             trackStreamingService.streamTracks(
diff --git a/src/main/java/gc/mda/signal_batch/monitoring/controller/QueryMetricsController.java b/src/main/java/gc/mda/signal_batch/monitoring/controller/QueryMetricsController.java
index c3b09de..5afd5fc 100644
--- a/src/main/java/gc/mda/signal_batch/monitoring/controller/QueryMetricsController.java
+++ b/src/main/java/gc/mda/signal_batch/monitoring/controller/QueryMetricsController.java
@@ -160,7 +160,8 @@ public class QueryMetricsController {
     @GetMapping("/timeseries")
     @Operation(summary = "쿼리 메트릭 시계열", description = "시간별/일별 버킷 집계 + Top 10 클라이언트")
     public Map<String, Object> getTimeSeries(
-            @Parameter(description = "조회 기간 (일)") @RequestParam(defaultValue = "7") int days) {
+            @Parameter(description = "조회 기간 (일)") @RequestParam(defaultValue = "7") int days,
+            @Parameter(description = "Top 클라이언트 그룹 기준 (ip | id)") @RequestParam(defaultValue = "ip") String groupBy) {
 
         days = Math.min(days, 90);
         String granularity = days <= 7 ? "HOURLY" : "DAILY";
@@ -184,15 +185,17 @@ public class QueryMetricsController {
 
         List<Map<String, Object>> buckets = queryJdbcTemplate.queryForList(bucketSql);
 
+        boolean groupById = "id".equalsIgnoreCase(groupBy);
+        String clientColumn = groupById ? "client_id" : "client_ip";
         String topClientsSql = """
-                SELECT client_ip, COUNT(*) AS query_count,
+                SELECT %s AS client, COUNT(*) AS query_count,
                        COALESCE(AVG(elapsed_ms), 0) AS avg_elapsed_ms
                 FROM signal.t_query_metrics
                 WHERE created_at >= NOW() - INTERVAL '%d days'
-                  AND client_ip IS NOT NULL
-                GROUP BY client_ip
+                  AND %s IS NOT NULL
+                GROUP BY %s
                 ORDER BY query_count DESC LIMIT 10
-                """.formatted(days);
+                """.formatted(clientColumn, days, clientColumn, clientColumn);
 
         List<Map<String, Object>> topClients = queryJdbcTemplate.queryForList(topClientsSql);
 
@@ -200,6 +203,7 @@ public class QueryMetricsController {
         result.put("buckets", buckets);
         result.put("topClients", topClients);
         result.put("granularity", granularity);
+        result.put("groupBy", groupById ? "id" : "ip");
 
         return result;
     }
diff --git a/src/main/java/gc/mda/signal_batch/monitoring/service/QueryMetricsBufferService.java b/src/main/java/gc/mda/signal_batch/monitoring/service/QueryMetricsBufferService.java
index 73fb889..0e7b0c0 100644
--- a/src/main/java/gc/mda/signal_batch/monitoring/service/QueryMetricsBufferService.java
+++ b/src/main/java/gc/mda/signal_batch/monitoring/service/QueryMetricsBufferService.java
@@ -32,7 +32,7 @@ public class QueryMetricsBufferService {
                 unique_vessels, total_tracks, total_points, points_after_simplify,
                 total_chunks, response_bytes,
                 elapsed_ms, db_query_ms, simplify_ms, backpressure_events,
-                status, client_ip
+                status, client_ip, client_id
             ) VALUES (
                 ?, ?, ?, now(),
                 ?, ?, ?, ?, ?,
@@ -40,7 +40,7 @@ public class QueryMetricsBufferService {
                 ?, ?, ?, ?,
                 ?, ?,
                 ?, ?, ?, ?,
-                ?, ?
+                ?, ?, ?
             )
             """;
 
@@ -73,6 +73,27 @@ public class QueryMetricsBufferService {
         }
     }
 
+    @PostConstruct
+    void ensureClientIdColumn() {
+        try {
+            queryJdbcTemplate.execute("""
+                    DO $$
+                    BEGIN
+                        IF NOT EXISTS (
+                            SELECT 1 FROM information_schema.columns
+                            WHERE table_schema = 'signal' AND table_name = 't_query_metrics' AND column_name = 'client_id'
+                        ) THEN
+                            ALTER TABLE signal.t_query_metrics ADD COLUMN client_id VARCHAR(100);
+                            CREATE INDEX IF NOT EXISTS idx_query_metrics_client_id ON signal.t_query_metrics(client_id, created_at);
+                        END IF;
+                    END $$
+                    """);
+            log.info("t_query_metrics client_id column ensured");
+        } catch (Exception e) {
+            log.warn("Failed to ensure client_id column: {}", e.getMessage());
+        }
+    }
+
     /**
      * 메트릭 레코드를 버퍼에 추가 (lock-free)
      */
@@ -119,7 +140,7 @@ public class QueryMetricsBufferService {
                 m.getUniqueVessels(), m.getTotalTracks(), m.getTotalPoints(), m.getPointsAfterSimplify(),
                 m.getTotalChunks(), m.getResponseBytes(),
                 m.getElapsedMs(), m.getDbQueryMs(), m.getSimplifyMs(), m.getBackpressureEvents(),
-                m.getStatus(), m.getClientIp()
+                m.getStatus(), m.getClientIp(), m.getClientId()
         };
     }
 
diff --git a/src/main/java/gc/mda/signal_batch/monitoring/service/QueryMetricsService.java b/src/main/java/gc/mda/signal_batch/monitoring/service/QueryMetricsService.java
index 8ec4b6f..d7a3ca8 100644
--- a/src/main/java/gc/mda/signal_batch/monitoring/service/QueryMetricsService.java
+++ b/src/main/java/gc/mda/signal_batch/monitoring/service/QueryMetricsService.java
@@ -131,5 +131,6 @@ public class QueryMetricsService {
         private final int backpressureEvents;
         private final String status;
         private final String clientIp;
+        private final String clientId;
     }
 }