diff --git a/analysis/geoip.py b/analysis/geoip.py
index 076b42b..ca9e832 100644
--- a/analysis/geoip.py
+++ b/analysis/geoip.py
@@ -12,6 +12,7 @@ import bisect
 import gzip
 import logging
 import shutil
+import tempfile
 from pathlib import Path
 from typing import Optional
 
@@ -107,11 +108,24 @@ def _load_mmdb() -> None:
 
     try:
         import maxminddb
-        _mmdb_city = maxminddb.open_database(city_path)
+
+        # maxminddb C extension cannot handle non-ASCII Windows paths.
+        # Workaround: copy MMDB files to a temp dir with ASCII-only path.
+        _tmp_dir = Path(tempfile.gettempdir()) / 'tianxuan_geoip'
+        _tmp_dir.mkdir(parents=True, exist_ok=True)
+
+        _tmp_city = _tmp_dir / 'GeoLite2-City.mmdb'
+        if not _tmp_city.exists() or _tmp_city.stat().st_size != city_path.stat().st_size:
+            logger.info('[GEOIP] copying MMDB to ASCII-safe temp dir …')
+            shutil.copy2(city_path, _tmp_city)
+        _mmdb_city = maxminddb.open_database(str(_tmp_city))
         logger.info('[GEOIP] loaded GeoLite2-City.mmdb (MMDB format)')
 
         if asn_path.exists():
-            _mmdb_asn = maxminddb.open_database(asn_path)
+            _tmp_asn = _tmp_dir / 'GeoLite2-ASN.mmdb'
+            if not _tmp_asn.exists() or _tmp_asn.stat().st_size != asn_path.stat().st_size:
+                shutil.copy2(asn_path, _tmp_asn)
+            _mmdb_asn = maxminddb.open_database(str(_tmp_asn))
             logger.info('[GEOIP] loaded GeoLite2-ASN.mmdb (ISP/ORG)')
     except Exception as e:
         logger.warning('[GEOIP] failed to open MMDB: %s', e)
diff --git a/simple_analysis/views.py b/simple_analysis/views.py
index ee1018d..72a4782 100644
--- a/simple_analysis/views.py
+++ b/simple_analysis/views.py
@@ -792,11 +792,12 @@ def _cluster_network(entry: dict, df: pl.DataFrame, meta: dict,
     logger.info('Network clustering: %d unique IPs from %d records', n_nodes, len(df))
 
     # ── 2. GeoIP 解析所有 IP ───────────────────────────────────────────
+    # MMDB优先（高精度），upload时的geo_cache兜底（低精度文本回退）
     node_geo = {}  # ip → {lat, lon, city, country, isp, org}
     for ip in unique_ips:
-        info = geo_cache.get(ip)
+        info = geoip_lookup(ip)  # 优先用当前加载的MMDB数据库
         if not info:
-            info = geoip_lookup(ip)
+            info = geo_cache.get(ip)  # 回退到上传时的缓存
         if info:
             node_geo[ip] = info