diff --git a/backend/app/services/batch_inspection_service.py b/backend/app/services/batch_inspection_service.py
index fd656d1..4b91d4b 100644
--- a/backend/app/services/batch_inspection_service.py
+++ b/backend/app/services/batch_inspection_service.py
@@ -63,9 +63,13 @@ class BatchInspectionService:
 
         batch_inspection_id = str(uuid.uuid4())
 
-        # Build discovered_pages documents
+        # Build discovered_pages documents (중복 URL 제거)
         discovered_pages = []
+        seen_urls: set[str] = set()
         for url in urls:
+            if url in seen_urls:
+                continue
+            seen_urls.add(url)
             discovered_pages.append({
                 "url": url,
                 "depth": 0,
@@ -76,6 +80,8 @@ class BatchInspectionService:
                 "overall_score": None,
                 "grade": None,
             })
+        # 중복 제거된 URL 목록으로 갱신
+        urls = list(seen_urls)
 
         # Create initial document
         doc = {
diff --git a/backend/app/services/link_crawler.py b/backend/app/services/link_crawler.py
index bfc388f..2253e1f 100644
--- a/backend/app/services/link_crawler.py
+++ b/backend/app/services/link_crawler.py
@@ -39,16 +39,21 @@ def normalize_url(url: str) -> str:
     - Remove fragment (#...)
     - Remove trailing slash (except for root path)
     - Lowercase scheme and netloc
+    - Strip www. prefix for consistent deduplication
+    - Remove common tracking query parameters
     """
     parsed = urlparse(url)
 
     # Remove fragment
     normalized = parsed._replace(fragment="")
 
-    # Lowercase scheme and netloc
+    # Lowercase scheme and netloc, strip www.
+    netloc = normalized.netloc.lower()
+    if netloc.startswith("www."):
+        netloc = netloc[4:]
     normalized = normalized._replace(
         scheme=normalized.scheme.lower(),
-        netloc=normalized.netloc.lower(),
+        netloc=netloc,
     )
 
     # Remove trailing slash (but keep "/" for root path)
@@ -57,6 +62,17 @@ def normalize_url(url: str) -> str:
         path = path.rstrip("/")
     normalized = normalized._replace(path=path)
 
+    # Remove common tracking query parameters
+    if normalized.query:
+        from urllib.parse import parse_qs, urlencode
+        _TRACKING_PARAMS = {
+            "utm_source", "utm_medium", "utm_campaign", "utm_term",
+            "utm_content", "ref", "fbclid", "gclid", "mc_cid", "mc_eid",
+        }
+        params = parse_qs(normalized.query, keep_blank_values=True)
+        filtered = {k: v for k, v in params.items() if k.lower() not in _TRACKING_PARAMS}
+        normalized = normalized._replace(query=urlencode(filtered, doseq=True))
+
     return urlunparse(normalized)
 
 
diff --git a/backend/app/services/site_inspection_service.py b/backend/app/services/site_inspection_service.py
index 149e918..91eb0b2 100644
--- a/backend/app/services/site_inspection_service.py
+++ b/backend/app/services/site_inspection_service.py
@@ -302,9 +302,13 @@ class SiteInspectionService:
             if not discovered:
                 raise ValueError("크롤링 결과가 없습니다. URL을 확인해주세요.")
 
-            # Build discovered_pages documents
+            # Build discovered_pages documents (중복 URL 제거)
             discovered_pages = []
+            seen_urls: set[str] = set()
             for page in discovered:
+                if page["url"] in seen_urls:
+                    continue
+                seen_urls.add(page["url"])
                 discovered_pages.append({
                     "url": page["url"],
                     "depth": page["depth"],
@@ -444,14 +448,6 @@ class SiteInspectionService:
         """Run inspection for a single discovered page."""
         inspection_id = str(uuid.uuid4())
 
-        # Publish page_start event
-        await self._publish_site_event(site_inspection_id, {
-            "event_type": "page_start",
-            "site_inspection_id": site_inspection_id,
-            "page_url": page_url,
-            "page_index": page_index,
-        })
-
         # Mark page as inspecting in MongoDB
         await self.db.site_inspections.update_one(
             {