diff --git a/core/huya/app_login.py b/core/huya/app_login.py
index 0c7277c..d68fed5 100644
--- a/core/huya/app_login.py
+++ b/core/huya/app_login.py
@@ -36,7 +36,7 @@ from loguru import logger
 
 from .cert_forge import build_p1, decrypt_cert, forge_cert, parse_p1
 from .cookie_utils import normalize_huya_cookie
-from .device_fingerprint import get_huya_sdid
+from .device_fingerprint import account_state_dir, get_huya_sdid
 from .device_profile import get_profile
 from .dfp_register import DfpRegistrationError, register_device
 from .envelope_forge import Envelope
@@ -445,7 +445,10 @@ class HuyaAppPasswordLogin:
 
         # 4) 模拟扫码绑定四步流获取 biztoken
         try:
-            sdid_obj = get_huya_sdid(allow_fallback=True)
+            # 一号一设备: sdid 状态按账号隔离 (默认全局目录会让所有账号共享
+            # 同一份 hydevice 设备状态, 服务端可跨账号关联 — 见 R40 缺口修复)
+            sdid_obj = get_huya_sdid(allow_fallback=True,
+                                     state_dir=account_state_dir(self.username))
             sdid = sdid_obj.sdid if sdid_obj else ""
             pc = QrRole(pc=True, sdid=sdid, proxies=self.proxies)
             ph = QrRole(pc=False, sdid=sdid, proxies=self.proxies)
diff --git a/core/huya/device_fingerprint.py b/core/huya/device_fingerprint.py
index f3ce002..e68fc2e 100644
--- a/core/huya/device_fingerprint.py
+++ b/core/huya/device_fingerprint.py
@@ -20,6 +20,17 @@ FINGERPRINT_DIR = Path(__file__).parent / "fingerprint"
 RUNNER_JS = FINGERPRINT_DIR / "runner.js"
 SDID_PREFIX = "__SDID__"
 
+# 每账号独立的 hydevice localStorage 状态目录 (一号一设备的关键):
+# 默认全局临时目录会让所有账号共用同一份设备采集状态 → sdid/40hex hdid 同源,
+# 服务端可跨账号关联设备。按账号分目录后, node 链路为每个账号维护独立"设备"。
+FP_STATE_ROOT = Path(__file__).resolve().parents[2] / "data" / "huya_fp_states"
+
+
+def account_state_dir(account: str) -> Path:
+    """账号专属指纹状态目录 (持久化, 保证同一账号多次登录是同一台'设备')。"""
+    safe = "".join(c if c.isalnum() or c in "-_." else "_" for c in (account or "anon"))[:64]
+    return FP_STATE_ROOT / safe
+
 DEFAULT_TIMEOUT = (8, 40)
 
 
@@ -103,7 +114,9 @@ def get_huya_sdid(
 
     Args:
         app_id: 虎牙应用 id，App 场景 5008。
-        state_dir: localStorage 持久化目录（保持设备一致性），None 用临时目录。
+        state_dir: localStorage 持久化目录（保持设备一致性）。None 用全局临时目录
+            (仅单设备场景可用); 多账号请传 account_state_dir(account) 实现
+            一号一设备 — 同账号多次登录复用同一份设备状态。
         allow_fallback: node 失败时是否降级为旧版无指纹方式。
     Returns:
         HuyaSdidResult(sdid, source, message)，source 为 fingerprint/fallback/none。
diff --git a/core/huya/login.py b/core/huya/login.py
index e8541ff..ebdbeb6 100644
--- a/core/huya/login.py
+++ b/core/huya/login.py
@@ -226,10 +226,12 @@ class HuyaPasswordLogin:
 
     def prepare_device(self) -> str:
         """获取虎牙风控 sdid（优先 hydevice 高信任指纹，失败降级旧版）。"""
-        from .device_fingerprint import get_huya_sdid
+        from .device_fingerprint import account_state_dir, get_huya_sdid
 
         try:
-            result = get_huya_sdid(app_id="5008", timeout=self.timeout)
+            # 一号一设备: 每账号独立 hydevice 状态, sdid/40hex hdid 不跨账号同源
+            result = get_huya_sdid(app_id="5008", timeout=self.timeout,
+                                   state_dir=account_state_dir(self.username))
             if result.sdid:
                 self.sdid = result.sdid
                 self.sdid_source = result.source