diff --git a/app/api/documents.py b/app/api/documents.py
index 31444d7..6a9ac08 100644
--- a/app/api/documents.py
+++ b/app/api/documents.py
@@ -37,6 +37,7 @@ class DocumentResponse(BaseModel):
     ai_tags: list | None
     ai_summary: str | None
     user_note: str | None
+    edit_url: str | None
     preview_status: str | None
     source_channel: str | None
     data_origin: str | None
@@ -63,6 +64,7 @@ class DocumentUpdate(BaseModel):
     ai_sub_group: str | None = None
     ai_tags: list | None = None
     user_note: str | None = None
+    edit_url: str | None = None
     source_channel: str | None = None
     data_origin: str | None = None
 
diff --git a/app/models/document.py b/app/models/document.py
index 99e7499..fa13499 100644
--- a/app/models/document.py
+++ b/app/models/document.py
@@ -47,6 +47,9 @@ class Document(Base):
     # 사용자 메모
     user_note: Mapped[str | None] = mapped_column(Text)
 
+    # 외부 편집 URL
+    edit_url: Mapped[str | None] = mapped_column(Text)
+
     # 미리보기
     preview_status: Mapped[str | None] = mapped_column(String(20), default="none")
     preview_hash: Mapped[str | None] = mapped_column(String(64))
diff --git a/frontend/src/lib/components/DocumentViewer.svelte b/frontend/src/lib/components/DocumentViewer.svelte
index 216d649..8393067 100644
--- a/frontend/src/lib/components/DocumentViewer.svelte
+++ b/frontend/src/lib/components/DocumentViewer.svelte
@@ -26,12 +26,10 @@
   }
 
   function getEditUrl(doc) {
-    if (['odoc', 'osheet', 'docx', 'xlsx', 'pptx', 'odt', 'ods', 'odp'].includes(doc.file_format)) {
-      return `https://link.hyungi.net`;
-    }
-    if (['dwg', 'dxf'].includes(doc.file_format)) {
-      return 'https://web.autocad.com';
-    }
+    // DB에 저장된 편집 URL 우선
+    if (doc.edit_url) return doc.edit_url;
+    // CAD는 AutoCAD Web
+    if (['dwg', 'dxf'].includes(doc.file_format)) return 'https://web.autocad.com';
     return null;
   }
 
diff --git a/frontend/src/lib/components/PreviewPanel.svelte b/frontend/src/lib/components/PreviewPanel.svelte
index de9459c..6c14633 100644
--- a/frontend/src/lib/components/PreviewPanel.svelte
+++ b/frontend/src/lib/components/PreviewPanel.svelte
@@ -16,12 +16,18 @@
   let newTag = $state('');
   let tagEditing = $state(false);
 
-  // doc 변경 시 메모 초기화
+  // 편집 URL
+  let editUrlText = $state('');
+  let editUrlEditing = $state(false);
+
+  // doc 변경 시 초기화
   $effect(() => {
     if (doc) {
       noteText = doc.user_note || '';
+      editUrlText = doc.edit_url || '';
       noteEditing = false;
       tagEditing = false;
+      editUrlEditing = false;
       newTag = '';
     }
   });
@@ -43,6 +49,20 @@
     }
   }
 
+  async function saveEditUrl() {
+    try {
+      await api(`/documents/${doc.id}`, {
+        method: 'PATCH',
+        body: JSON.stringify({ edit_url: editUrlText.trim() || null }),
+      });
+      doc.edit_url = editUrlText.trim() || null;
+      editUrlEditing = false;
+      addToast('success', '편집 URL 저장됨');
+    } catch (err) {
+      addToast('error', '편집 URL 저장 실패');
+    }
+  }
+
   async function addTag() {
     const tag = newTag.trim();
     if (!tag) return;
@@ -138,6 +158,32 @@
       {/if}
     </div>
 
+    <!-- 편집 URL -->
+    <div>
+      <h4 class="text-xs font-semibold text-[var(--text-dim)] uppercase mb-1.5">편집 링크</h4>
+      {#if editUrlEditing}
+        <div class="flex gap-1">
+          <input
+            bind:value={editUrlText}
+            placeholder="Synology Drive URL 붙여넣기..."
+            class="flex-1 px-2 py-1 bg-[var(--bg)] border border-[var(--border)] rounded text-xs text-[var(--text)] outline-none focus:border-[var(--accent)]"
+          />
+          <button onclick={saveEditUrl} class="px-2 py-1 text-xs bg-[var(--accent)] text-white rounded">저장</button>
+          <button onclick={() => { editUrlEditing = false; editUrlText = doc.edit_url || ''; }} class="px-2 py-1 text-xs text-[var(--text-dim)]">취소</button>
+        </div>
+      {:else if doc.edit_url}
+        <div class="flex items-center gap-1">
+          <a href={doc.edit_url} target="_blank" class="text-xs text-[var(--accent)] truncate hover:underline">{doc.edit_url}</a>
+          <button onclick={() => editUrlEditing = true} class="text-[10px] text-[var(--text-dim)] hover:text-[var(--text)]">수정</button>
+        </div>
+      {:else}
+        <button
+          onclick={() => editUrlEditing = true}
+          class="text-xs text-[var(--text-dim)] hover:text-[var(--accent)]"
+        >+ URL 추가</button>
+      {/if}
+    </div>
+
     <!-- 태그 -->
     <div>
       <h4 class="text-xs font-semibold text-[var(--text-dim)] uppercase mb-1.5">태그</h4>
diff --git a/migrations/006_edit_url.sql b/migrations/006_edit_url.sql
new file mode 100644
index 0000000..4189a27
--- /dev/null
+++ b/migrations/006_edit_url.sql
@@ -0,0 +1,2 @@
+-- 외부 편집 URL (Synology Drive 공유 링크 등)
+ALTER TABLE documents ADD COLUMN IF NOT EXISTS edit_url TEXT;