diff --git a/.github/workflows/release-dev.yml b/.github/workflows/release-dev.yml
index e825816..483c86b 100644
--- a/.github/workflows/release-dev.yml
+++ b/.github/workflows/release-dev.yml
@@ -179,6 +179,10 @@ jobs:
           ls -la textlingo-desktop/src-tauri/binaries
         shell: bash
 
+      - name: stage PDF offline assets
+        run: python script/build_pdf_offline_assets.py
+        shell: bash
+
       - uses: tauri-apps/tauri-action@v0
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 559fa02..2e6b8bd 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -176,6 +176,10 @@ jobs:
           ls -la textlingo-desktop/src-tauri/binaries
         shell: bash
 
+      - name: stage PDF offline assets
+        run: python script/build_pdf_offline_assets.py
+        shell: bash
+
       - uses: tauri-apps/tauri-action@v0
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
diff --git a/script/build_pdf_offline_assets.py b/script/build_pdf_offline_assets.py
new file mode 100644
index 0000000..90a1150
--- /dev/null
+++ b/script/build_pdf_offline_assets.py
@@ -0,0 +1,56 @@
+#!/usr/bin/env python3
+"""Stage a subset of babeldoc offline assets into the Tauri resources dir.
+
+The desktop app ships the DocLayout layout model plus the CJK serif fonts so the
+first PDF translation runs without a network download (which is slow/flaky and
+made the app look frozen). We deliberately bundle only what the OpenKoto
+translation path actually uses — the layout model (always) and one serif font
+per CJK target language plus the GoNoto fallback — instead of babeldoc's full
+~243 MB font set.
+
+Run this AFTER `pip install -e ./textlingo-desktop/pdf-sidecar` (which installs
+the pinned babeldoc), and BEFORE the Tauri bundle step.
+"""
+
+import shutil
+import sys
+from pathlib import Path
+
+from babeldoc.assets.assets import (
+    get_doclayout_onnx_model_path,
+    get_font_and_metadata,
+)
+
+# Serif fonts matching high_level.download_remote_fonts() for zh-CN / zh-TW /
+# ja / ko, plus the GoNoto fallback used for every other language.
+FONTS = [
+    "GoNotoKurrent-Regular.ttf",
+    "SourceHanSerifCN-Regular.ttf",
+    "SourceHanSerifTW-Regular.ttf",
+    "SourceHanSerifJP-Regular.ttf",
+    "SourceHanSerifKR-Regular.ttf",
+]
+
+
+def main() -> int:
+    repo_root = Path(__file__).resolve().parent.parent
+    stage = repo_root / "textlingo-desktop" / "src-tauri" / "resources" / "pdf-assets"
+    (stage / "models").mkdir(parents=True, exist_ok=True)
+    (stage / "fonts").mkdir(parents=True, exist_ok=True)
+
+    model = Path(get_doclayout_onnx_model_path())
+    shutil.copy2(model, stage / "models" / model.name)
+    print(f"staged model: {model.name}")
+
+    for font in FONTS:
+        path, _ = get_font_and_metadata(font)
+        shutil.copy2(Path(path), stage / "fonts" / font)
+        print(f"staged font: {font}")
+
+    total = sum(p.stat().st_size for p in stage.rglob("*") if p.is_file())
+    print(f"offline assets staged at {stage} ({total / 1024 / 1024:.1f} MB)")
+    return 0
+
+
+if __name__ == "__main__":
+    sys.exit(main())
diff --git a/textlingo-desktop/package.json b/textlingo-desktop/package.json
index 86b647c..912a9af 100644
--- a/textlingo-desktop/package.json
+++ b/textlingo-desktop/package.json
@@ -1,7 +1,7 @@
 {
   "name": "openkoto-desktop",
   "private": true,
-  "version": "0.6.12",
+  "version": "0.6.13",
   "type": "module",
   "scripts": {
     "dev": "vite",
diff --git a/textlingo-desktop/pdf-sidecar/openkoto_pdf_translator/pdf2zh.py b/textlingo-desktop/pdf-sidecar/openkoto_pdf_translator/pdf2zh.py
index dd9c4ab..2130034 100644
--- a/textlingo-desktop/pdf-sidecar/openkoto_pdf_translator/pdf2zh.py
+++ b/textlingo-desktop/pdf-sidecar/openkoto_pdf_translator/pdf2zh.py
@@ -58,6 +58,43 @@ def _emit_openkoto_progress(progress) -> None:
         pass
 
 
+def _seed_offline_assets() -> None:
+    """Copy bundled DocLayout model / fonts into babeldoc's cache so the first
+    translation does not need to download them.
+
+    The desktop app sets OPENKOTO_OFFLINE_ASSETS_DIR to a resource folder laid
+    out as ``<dir>/models/*.onnx`` and ``<dir>/fonts/*.ttf``. Best-effort: any
+    failure just falls back to babeldoc's normal on-demand download.
+    """
+    src_dir = os.environ.get("OPENKOTO_OFFLINE_ASSETS_DIR")
+    if not src_dir or not os.path.isdir(src_dir):
+        return
+    try:
+        import shutil
+        from babeldoc.const import get_cache_file_path
+
+        for sub_folder in ("models", "fonts"):
+            type_dir = os.path.join(src_dir, sub_folder)
+            if not os.path.isdir(type_dir):
+                continue
+            for name in os.listdir(type_dir):
+                src = os.path.join(type_dir, name)
+                if not os.path.isfile(src):
+                    continue
+                # get_cache_file_path creates the destination sub-folder for us.
+                dst = str(get_cache_file_path(name, sub_folder))
+                if os.path.exists(dst):
+                    continue
+                shutil.copy2(src, dst)
+                print(
+                    f"[PDF] seeded offline asset: {sub_folder}/{name}",
+                    file=sys.stderr,
+                    flush=True,
+                )
+    except Exception as e:
+        print(f"[PDF] offline asset seeding skipped: {e}", file=sys.stderr, flush=True)
+
+
 def create_parser() -> argparse.ArgumentParser:
     parser = argparse.ArgumentParser(description=__doc__, add_help=True)
     parser.add_argument(
@@ -299,6 +336,10 @@ def main(args: Optional[List[str]] = None) -> int:
     if parsed_args.debug:
         log.setLevel(logging.DEBUG)
 
+    # Restore bundled offline assets (if shipped) before any model/font load so
+    # the first translation does not block on a network download.
+    _seed_offline_assets()
+
     if parsed_args.onnx:
         ModelInstance.value = OnnxModel(parsed_args.onnx)
     else:
diff --git a/textlingo-desktop/src-tauri/.gitignore b/textlingo-desktop/src-tauri/.gitignore
index b21bd68..4d47170 100644
--- a/textlingo-desktop/src-tauri/.gitignore
+++ b/textlingo-desktop/src-tauri/.gitignore
@@ -5,3 +5,8 @@
 # Generated by Tauri
 # will have schema files for capabilities auto-completion
 /gen/schemas
+
+# PDF offline assets are generated in CI (script/build_pdf_offline_assets.py),
+# not committed (~95 MB). Keep the folder + README, ignore the binaries.
+/resources/pdf-assets/models/
+/resources/pdf-assets/fonts/
diff --git a/textlingo-desktop/src-tauri/Cargo.lock b/textlingo-desktop/src-tauri/Cargo.lock
index a2b0fbc..99915c1 100644
--- a/textlingo-desktop/src-tauri/Cargo.lock
+++ b/textlingo-desktop/src-tauri/Cargo.lock
@@ -2859,7 +2859,7 @@ dependencies = [
 
 [[package]]
 name = "openkoto-desktop"
-version = "0.6.12"
+version = "0.6.13"
 dependencies = [
  "base64 0.22.1",
  "chrono",
diff --git a/textlingo-desktop/src-tauri/Cargo.toml b/textlingo-desktop/src-tauri/Cargo.toml
index 67c930a..5765aa1 100644
--- a/textlingo-desktop/src-tauri/Cargo.toml
+++ b/textlingo-desktop/src-tauri/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "openkoto-desktop"
-version = "0.6.12"
+version = "0.6.13"
 description = "OpenKoto Desktop - AI-powered Article Reader"
 authors = ["OpenKoto Team"]
 edition = "2021"
diff --git a/textlingo-desktop/src-tauri/resources/pdf-assets/README.md b/textlingo-desktop/src-tauri/resources/pdf-assets/README.md
new file mode 100644
index 0000000..01dd113
--- /dev/null
+++ b/textlingo-desktop/src-tauri/resources/pdf-assets/README.md
@@ -0,0 +1,20 @@
+# PDF offline assets
+
+This folder ships the babeldoc assets the PDF translator needs so the **first**
+translation does not have to download them (DocLayout layout model + CJK serif
+fonts). It exists so packaged builds can run PDF translation offline.
+
+The actual `models/*.onnx` and `fonts/*.ttf` files are **generated in CI**, not
+committed (they are ~95 MB). They are produced by:
+
+```
+python script/build_pdf_offline_assets.py
+```
+
+which must run after `pip install -e ./textlingo-desktop/pdf-sidecar` and before
+the Tauri bundle step. The Rust side points the sidecar at this folder via the
+`OPENKOTO_OFFLINE_ASSETS_DIR` env var; the sidecar copies the files into
+babeldoc's cache on first run (see `_seed_offline_assets` in `pdf2zh.py`).
+
+In local dev builds where these files are absent, the sidecar simply falls back
+to babeldoc's normal on-demand download.
diff --git a/textlingo-desktop/src-tauri/src/commands.rs b/textlingo-desktop/src-tauri/src/commands.rs
index 2574dd4..1346de0 100644
--- a/textlingo-desktop/src-tauri/src/commands.rs
+++ b/textlingo-desktop/src-tauri/src/commands.rs
@@ -3023,6 +3023,22 @@ pub async fn translate_pdf_document(
         envs.push(("OPENKOTO_BASE_URL", url));
     }
 
+    // Point the sidecar at bundled offline assets (DocLayout model + CJK fonts)
+    // so the first translation doesn't block on a network download. Absent in
+    // dev builds, in which case the sidecar falls back to on-demand download.
+    if let Ok(resource_dir) = app_handle.path().resource_dir() {
+        for candidate in ["resources/pdf-assets", "pdf-assets"] {
+            let dir = resource_dir.join(candidate);
+            if dir.join("models").is_dir() || dir.join("fonts").is_dir() {
+                envs.push((
+                    "OPENKOTO_OFFLINE_ASSETS_DIR",
+                    dir.to_string_lossy().to_string(),
+                ));
+                break;
+            }
+        }
+    }
+
     let sidecar = pdf_sidecar::resolve_pdf_sidecar(&app_handle)
         .map_err(|e| format!("PDF sidecar error: {e}"))?;
     let cmd = sidecar.program;
diff --git a/textlingo-desktop/src-tauri/tauri.conf.json b/textlingo-desktop/src-tauri/tauri.conf.json
index e9fed50..14ad58f 100644
--- a/textlingo-desktop/src-tauri/tauri.conf.json
+++ b/textlingo-desktop/src-tauri/tauri.conf.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://schema.tauri.app/config/2",
   "productName": "OpenKoto Desktop",
-  "version": "0.6.12",
+  "version": "0.6.13",
   "identifier": "com.openkoto.desktop",
   "build": {
     "beforeDevCommand": "npm run dev",
@@ -51,6 +51,9 @@
       "binaries/ffmpeg",
       "binaries/openkoto-pdf-translator"
     ],
+    "resources": [
+      "resources/pdf-assets"
+    ],
     "macOS": {
       "entitlements": "entitlements.plist"
     }