diff --git a/docs/changelog/2026-06-05-install-wizard-docker-redis.md b/docs/changelog/2026-06-05-install-wizard-docker-redis.md
new file mode 100644
index 00000000..65a69e9d
--- /dev/null
+++ b/docs/changelog/2026-06-05-install-wizard-docker-redis.md
@@ -0,0 +1,27 @@
+# 2026-06-05 — 安装向导 Docker Redis 检测修复
+
+## 摘要
+
+修复 Docker 部署下安装向导步骤 2 误报 `127.0.0.1:6379 Connection refused`。
+Compose 栈中 Redis 仅在容器内网 `redis:6379`，未映射宿主机端口。
+
+## 变更
+
+- `server/api/install.py`：`env-check` 读取 `NEXUS_REDIS_URL` / `REDIS_HOST`
+- 返回 `docker_defaults`（db_host=mysql, redis_host=redis 等）供步骤 3 预填
+- `web/app/install.html`：环境检测后自动应用 `docker_defaults`
+
+## 验证
+
+- Docker 容器内 `env-check` Redis 应对 `redis:6379` 显示 ✓
+- 步骤 3 数据库主机应为 `mysql`，Redis 为 `redis`
+
+## 已部署容器热修
+
+```bash
+cd /opt/nexus && git pull
+bash deploy/sync-install-wizard-to-container.sh
+docker compose -f docker/docker-compose.prod.yml --env-file docker/.env.prod restart nexus
+```
+
+或 `nexus-1panel.sh upgrade` 重建镜像。
diff --git a/server/api/install.py b/server/api/install.py
index 6227bb26..31f0fc8c 100644
--- a/server/api/install.py
+++ b/server/api/install.py
@@ -12,7 +12,7 @@ import logging
 import subprocess
 from pathlib import Path
 from datetime import datetime, timezone
-from urllib.parse import quote_plus
+from urllib.parse import quote_plus, urlparse
 
 from fastapi import APIRouter, HTTPException
 from pydantic import BaseModel
@@ -98,6 +98,36 @@ def _build_redis_url(req: InitDbRequest) -> str:
     return url
 
 
+def _resolve_redis_probe() -> tuple[str, int, str | None]:
+    """Redis target for install wizard health check (Docker uses redis:6379, not host loopback)."""
+    url = os.environ.get("NEXUS_REDIS_URL", "").strip()
+    if url:
+        parsed = urlparse(url)
+        host = parsed.hostname or "127.0.0.1"
+        port = parsed.port or 6379
+        return host, port, parsed.password
+
+    host = os.environ.get("REDIS_HOST", "127.0.0.1")
+    port = int(os.environ.get("REDIS_PORT", "6379"))
+    return host, port, None
+
+
+def _docker_wizard_defaults() -> dict[str, str] | None:
+    """Prefill install step 3 when running inside docker-compose.prod.yml."""
+    if os.environ.get("NEXUS_DOCKER_WRITE_ENV") != "1" and not os.environ.get("REDIS_HOST"):
+        return None
+    rh, rp, _ = _resolve_redis_probe()
+    return {
+        "db_host": os.environ.get("MYSQL_HOST", "mysql"),
+        "db_port": os.environ.get("MYSQL_PORT", "3306"),
+        "db_name": "nexus",
+        "db_user": "nexus",
+        "redis_host": rh,
+        "redis_port": str(rp),
+        "redis_db": "0",
+    }
+
+
 def _install_keys_from_environment() -> tuple[str, str, str] | None:
     """Reuse keys pre-generated by Docker install (docker/.env.prod → compose env)."""
     import os
@@ -413,16 +443,23 @@ async def env_check():
             "pass": False,
         })
 
-    # Redis
+    # Redis — Docker Compose: redis:6379 (not published on host 127.0.0.1)
     redis_ok = False
     redis_msg = "未安装"
+    rh, rp, rpass = _resolve_redis_probe()
+    redis_label = f"{rh}:{rp}"
     try:
         import redis as rlib
         try:
-            r = rlib.Redis(host="127.0.0.1", port=6379, socket_timeout=0.5)
+            r = rlib.Redis(
+                host=rh,
+                port=rp,
+                password=rpass or None,
+                socket_timeout=0.5,
+            )
             r.ping()
             redis_ok = True
-            redis_msg = "✓ 已连接 127.0.0.1:6379"
+            redis_msg = f"✓ 已连接 {redis_label}"
         except Exception as e:
             redis_msg = f"连接失败: {e}"
     except ImportError:
@@ -460,7 +497,11 @@ async def env_check():
     })
 
     all_pass = all(c["pass"] for c in checks)
-    return {"checks": checks, "all_pass": all_pass}
+    payload: dict = {"checks": checks, "all_pass": all_pass}
+    defaults = _docker_wizard_defaults()
+    if defaults:
+        payload["docker_defaults"] = defaults
+    return payload
 
 
 @router.post("/init-db")
diff --git a/web/app/install.html b/web/app/install.html
index 56fa0947..6d388933 100644
--- a/web/app/install.html
+++ b/web/app/install.html
@@ -639,6 +639,9 @@ function installWizard() {
      const d = await r.json();
      this.envChecks = d.checks;
      this.envAllPass = d.all_pass;
+     if (d.docker_defaults) {
+      Object.assign(this.form, d.docker_defaults);
+     }
     }
    } catch(e) {
     this.error = '环境检测请求失败: ' + e.message;