diff --git a/blade-auth/src/main/java/org/springblade/auth/dto/IamSsoProfileResponse.java b/blade-auth/src/main/java/org/springblade/auth/dto/IamSsoProfileResponse.java
index d51f7f8..c2ff4f6 100644
--- a/blade-auth/src/main/java/org/springblade/auth/dto/IamSsoProfileResponse.java
+++ b/blade-auth/src/main/java/org/springblade/auth/dto/IamSsoProfileResponse.java
@@ -26,6 +26,7 @@
 package org.springblade.auth.dto;
 
 import com.fasterxml.jackson.annotation.JsonProperty;
+import com.fasterxml.jackson.annotation.JsonAlias;
 import lombok.Data;
 
 import java.util.Map;
@@ -43,6 +44,13 @@ public class IamSsoProfileResponse {
 	 */
 	private String id;
 
+	/**
+	 * IAM返回的本系统账号，部分部署直接返回在顶层。
+	 */
+	@JsonProperty("account_no")
+	@JsonAlias({"accountNo", "account", "username", "user_name"})
+	private String accountNo;
+
 	/**
 	 * IAM用户扩展属性
 	 */
@@ -54,12 +62,20 @@ public class IamSsoProfileResponse {
 	 * @return 本系统账号
 	 */
 	@JsonProperty(access = JsonProperty.Access.READ_ONLY)
-	public String getAccountNo() {
-		if (attributes == null) {
-			return null;
+	public String resolveAccountNo() {
+		if (accountNo != null && !accountNo.isBlank()) {
+			return accountNo;
 		}
-		Object accountNo = attributes.get("account_no");
-		return accountNo == null ? null : String.valueOf(accountNo);
+		if (attributes == null) {
+			return id;
+		}
+		for (String key : new String[]{"account_no", "accountNo", "account", "username", "user_name"}) {
+			Object value = attributes.get(key);
+			if (value != null && !String.valueOf(value).isBlank()) {
+				return String.valueOf(value);
+			}
+		}
+		return id;
 	}
 
 }
diff --git a/blade-auth/src/main/java/org/springblade/auth/granter/IamSsoTokenGranter.java b/blade-auth/src/main/java/org/springblade/auth/granter/IamSsoTokenGranter.java
index 6c6d279..c1dfecf 100644
--- a/blade-auth/src/main/java/org/springblade/auth/granter/IamSsoTokenGranter.java
+++ b/blade-auth/src/main/java/org/springblade/auth/granter/IamSsoTokenGranter.java
@@ -143,7 +143,7 @@ public class IamSsoTokenGranter extends AuthorizationCodeGranter {
 		}
 
 		IamSsoProfileResponse profileResponse = requestIamProfile(accessToken);
-		String accountNo = profileResponse.getAccountNo();
+		String accountNo = profileResponse.resolveAccountNo();
 		if (StringUtil.isBlank(accountNo)) {
 			log.warn("IAM统一身份认证用户信息缺少account_no，iamId={}", profileResponse.getId());
 			throw new UserInvalidException(OAuth2TokenConstant.USER_NOT_FOUND);
@@ -165,23 +165,32 @@ public class IamSsoTokenGranter extends AuthorizationCodeGranter {
 
 	private UserInfo loadOrCreateIamUser(OAuth2Request request, IamSsoProfileResponse profileResponse, String tenantId, String accountNo) {
 		R<UserInfo> result = userClient.userInfo(tenantId, accountNo);
-		if (result.isSuccess() && result.getData() != null) {
+		if (result.isSuccess() && hasUser(result.getData())) {
 			return result.getData();
 		}
-		log.info("IAM统一身份认证未匹配到本系统账号，开始自动创建用户，tenantId={}, accountNo={}", tenantId, accountNo);
+		log.info("IAM统一身份认证未匹配到本系统账号，开始自动创建用户，tenantId={}, accountNo={}, querySuccess={}",
+			tenantId, accountNo, result.isSuccess());
 		R<Boolean> saveResult = userClient.saveIamUser(buildIamUser(profileResponse, tenantId, accountNo));
 		if (!saveResult.isSuccess() || !Boolean.TRUE.equals(saveResult.getData())) {
 			log.warn("IAM统一身份认证自动创建用户失败，tenantId={}, accountNo={}, msg={}", tenantId, accountNo, saveResult.getMsg());
 			throw new UserInvalidException(OAuth2TokenConstant.USER_NOT_FOUND);
 		}
 		R<UserInfo> createdResult = userClient.userInfo(tenantId, accountNo);
-		if (!createdResult.isSuccess() || createdResult.getData() == null) {
+		if (!createdResult.isSuccess() || !hasUser(createdResult.getData())) {
 			log.warn("IAM统一身份认证自动创建用户后未查询到用户，tenantId={}, accountNo={}", tenantId, accountNo);
 			throw new UserInvalidException(OAuth2TokenConstant.USER_NOT_FOUND);
 		}
 		return createdResult.getData();
 	}
 
+	/**
+	 * Feign 返回成功时，data 仍可能是一个 user 为空的 UserInfo 包装对象。
+	 * IAM 登录必须确保本地用户实体存在，避免被误报为密码校验失败。
+	 */
+	private boolean hasUser(UserInfo userInfo) {
+		return userInfo != null && userInfo.getUser() != null;
+	}
+
 	private User buildIamUser(IamSsoProfileResponse profileResponse, String tenantId, String accountNo) {
 		User user = new User();
 		user.setTenantId(tenantId);
diff --git a/blade-auth/src/main/java/org/springblade/auth/handler/BladeAuthorizationHandler.java b/blade-auth/src/main/java/org/springblade/auth/handler/BladeAuthorizationHandler.java
index 1526d27..e6e793e 100644
--- a/blade-auth/src/main/java/org/springblade/auth/handler/BladeAuthorizationHandler.java
+++ b/blade-auth/src/main/java/org/springblade/auth/handler/BladeAuthorizationHandler.java
@@ -40,6 +40,7 @@ import org.springblade.core.tool.jackson.JsonUtil;
 import org.springblade.core.tool.utils.DateUtil;
 import org.springblade.core.tool.utils.DesUtil;
 import org.springblade.core.tool.utils.SM2Util;
+import org.springblade.core.tool.utils.StringUtil;
 import org.springblade.system.cache.SysCache;
 import org.springblade.system.pojo.entity.Tenant;
 
@@ -74,6 +75,10 @@ public class BladeAuthorizationHandler extends AbstractAuthorizationHandler {
 	 */
 	@Override
 	public OAuth2Validation preValidation(OAuth2Request request) {
+		// IAM授权码已经由外部身份系统完成认证，不读取或校验本地密码。
+		if (StringUtil.equals("iam_sso", request.getGrantType())) {
+			return new OAuth2Validation();
+		}
 		if (request.isPassword() || request.isCaptchaCode()) {
 			// 生产环境弱密码校验
 			if (bladeProperties.isProd() && isWeakPassword(request.getPassword())) {