diff --git a/backend/app/api/refresh.py b/backend/app/api/refresh.py
index 4963dba..438718f 100644
--- a/backend/app/api/refresh.py
+++ b/backend/app/api/refresh.py
@@ -46,11 +46,27 @@ def reseed_symbols() -> dict:
 
     호출 예 (Windows cmd):
         curl -X POST http://localhost:8000/api/refresh/seed/symbols
+
+    KRX 가 주말/장 마감 시간에 비정상 응답을 줄 때도 SEED 10 종목은 항상 보장하므로
+    엔드포인트는 200 을 돌려준다. 부분 성공 정보는 응답 body 에 담아 사용자가 판단.
     """
-    report = seed_symbols()
-    return {
-        "inserted": report.inserted,
-        "updated": report.updated,
-        "seed_marked": report.seed_marked,
-        "markets": report.markets,
-    }
+    try:
+        report = seed_symbols()
+        return {
+            "ok": True,
+            "inserted": report.inserted,
+            "updated": report.updated,
+            "seed_marked": report.seed_marked,
+            "markets": report.markets,
+        }
+    except Exception as e:  # noqa: BLE001
+        # seed_symbols 내부에서 다 잡지만, 만에 하나 외부로 새는 예외 (logger 포매터
+        # 자체 버그 등) 도 200 으로 흡수해서 SEED 10 만이라도 살리는 게 UX 목표.
+        return {
+            "ok": False,
+            "inserted": 0,
+            "updated": 0,
+            "seed_marked": 0,
+            "markets": {},
+            "error": repr(e)[:300],
+        }
diff --git a/backend/app/fetch/symbols_seed.py b/backend/app/fetch/symbols_seed.py
index 38357b6..9323106 100644
--- a/backend/app/fetch/symbols_seed.py
+++ b/backend/app/fetch/symbols_seed.py
@@ -78,8 +78,11 @@ def seed_symbols() -> SeedReport:
         _upsert_seed_tickers()
         seed_marked = len(SEED_TICKERS)
         logger.info("seed_symbols: seed-tickers upserted (%d)", seed_marked)
-    except Exception:  # noqa: BLE001
-        logger.exception("seed_symbols: seed-tickers upsert failed (critical)")
+    except Exception as e:  # noqa: BLE001
+        # logger.exception 은 Python 3.11 의 traceback 포매터가 pykrx 소스의 한글 주석
+        # 'df = 가...' 바이트를 만나면 UnicodeDecodeError 를 던지는 버그가 있어, 그 예외가
+        # try 밖으로 escape 해서 500 을 만든다. 그래서 traceback 안 찍는다.
+        logger.error("seed_symbols: seed-tickers upsert failed: %s", repr(e)[:300])
         seed_marked = 0
 
     # 2) KRX 전 종목 — fetch 실패해도 부분 성공 허용
@@ -92,8 +95,8 @@ def seed_symbols() -> SeedReport:
             for code, name in listing:
                 all_rows.append((code, name, market))
             logger.info("seed_symbols: KRX %s fetched (%d)", market, len(listing))
-        except Exception:  # noqa: BLE001
-            logger.exception("seed_symbols: KRX %s fetch failed — skip market", market)
+        except Exception as e:  # noqa: BLE001
+            logger.error("seed_symbols: KRX %s fetch failed — skip market: %s", market, repr(e)[:300])
             market_counts[market] = 0
 
     inserted = updated = 0
@@ -122,8 +125,8 @@ def seed_symbols() -> SeedReport:
                         inserted += 1
                     else:
                         updated += 1
-        except Exception:  # noqa: BLE001
-            logger.exception("seed_symbols: KRX bulk upsert failed (transaction rolled back)")
+        except Exception as e:  # noqa: BLE001
+            logger.error("seed_symbols: KRX bulk upsert failed (transaction rolled back): %s", repr(e)[:300])
 
     logger.info(
         "seed_symbols done: inserted=%d updated=%d seed_marked=%d markets=%s",