diff --git a/app/Http/Controllers/Juil/ConstructionSitePhotoController.php b/app/Http/Controllers/Juil/ConstructionSitePhotoController.php
index f48a99b0..5a2a05a8 100644
--- a/app/Http/Controllers/Juil/ConstructionSitePhotoController.php
+++ b/app/Http/Controllers/Juil/ConstructionSitePhotoController.php
@@ -2,6 +2,7 @@
 
 namespace App\Http\Controllers\Juil;
 
+use App\Helpers\AiTokenHelper;
 use App\Http\Controllers\Controller;
 use App\Models\Juil\ConstructionSitePhoto;
 use App\Services\ConstructionSitePhotoService;
@@ -233,4 +234,15 @@ public function downloadPhoto(Request $request, int $id, string $type): Response
             ->header('Content-Disposition', "{$disposition}; filename=\"{$encodedFilename}\"; filename*=UTF-8''{$encodedFilename}")
             ->header('Cache-Control', 'private, max-age=3600');
     }
+
+    public function logSttUsage(Request $request): JsonResponse
+    {
+        $validated = $request->validate([
+            'duration_seconds' => 'required|integer|min:1',
+        ]);
+
+        AiTokenHelper::saveSttUsage('공사현장사진대지-음성입력', $validated['duration_seconds']);
+
+        return response()->json(['success' => true]);
+    }
 }
diff --git a/resources/views/juil/construction-photos.blade.php b/resources/views/juil/construction-photos.blade.php
index 52ee209d..907c8474 100644
--- a/resources/views/juil/construction-photos.blade.php
+++ b/resources/views/juil/construction-photos.blade.php
@@ -25,6 +25,7 @@
     deletePhoto: (id, type) => `/juil/construction-photos/${id}/photo/${type}`,
     downloadPhoto: (id, type) => `/juil/construction-photos/${id}/download/${type}`,
     photoUrl: (id, type) => `/juil/construction-photos/${id}/download/${type}?inline=1`,
+    logSttUsage: '/juil/construction-photos/log-stt-usage',
 };
 
 const CSRF_TOKEN = document.querySelector('meta[name="csrf-token"]')?.content || '';
@@ -58,16 +59,30 @@ function VoiceInputButton({ onResult, disabled }) {
     const [recording, setRecording] = useState(false);
     const [interim, setInterim] = useState('');
     const recognitionRef = useRef(null);
+    const startTimeRef = useRef(null);
 
     const isSupported = typeof window !== 'undefined' &&
         (window.SpeechRecognition || window.webkitSpeechRecognition);
 
+    const logUsage = useCallback((startTime) => {
+        const duration = Math.max(1, Math.round((Date.now() - startTime) / 1000));
+        apiFetch(API.logSttUsage, {
+            method: 'POST',
+            headers: { 'Content-Type': 'application/json' },
+            body: JSON.stringify({ duration_seconds: duration }),
+        }).catch(() => {});
+    }, []);
+
     const stopRecording = useCallback(() => {
         recognitionRef.current?.stop();
         recognitionRef.current = null;
+        if (startTimeRef.current) {
+            logUsage(startTimeRef.current);
+            startTimeRef.current = null;
+        }
         setRecording(false);
         setInterim('');
-    }, []);
+    }, [logUsage]);
 
     const startRecording = useCallback(() => {
         const SR = window.SpeechRecognition || window.webkitSpeechRecognition;
@@ -96,12 +111,17 @@ function VoiceInputButton({ onResult, disabled }) {
         };
         recognition.onerror = () => stopRecording();
         recognition.onend = () => {
+            if (startTimeRef.current) {
+                logUsage(startTimeRef.current);
+                startTimeRef.current = null;
+            }
             setRecording(false);
             setInterim('');
             recognitionRef.current = null;
         };
 
         recognitionRef.current = recognition;
+        startTimeRef.current = Date.now();
         recognition.start();
         setRecording(true);
         setInterim('');
diff --git a/routes/web.php b/routes/web.php
index 19314e3b..460444e2 100644
--- a/routes/web.php
+++ b/routes/web.php
@@ -1325,5 +1325,6 @@
         Route::delete('/{id}', [ConstructionSitePhotoController::class, 'destroy'])->name('destroy');
         Route::delete('/{id}/photo/{type}', [ConstructionSitePhotoController::class, 'deletePhoto'])->name('delete-photo');
         Route::get('/{id}/download/{type}', [ConstructionSitePhotoController::class, 'downloadPhoto'])->name('download');
+        Route::post('/log-stt-usage', [ConstructionSitePhotoController::class, 'logSttUsage'])->name('log-stt-usage');
     });
 });