diff --git a/server/src/main/resources/application-dev.yml b/server/src/main/resources/application-dev.yml
index 3c063bf..f810bec 100644
--- a/server/src/main/resources/application-dev.yml
+++ b/server/src/main/resources/application-dev.yml
@@ -7,6 +7,11 @@ spring:
     driver-class-name: com.mysql.cj.jdbc.Driver
   flyway:
     enabled: true
+  servlet:
+    multipart:
+      # dev Debug EML multipart 上限必须不小于业务文件上限，避免请求进入 Controller 前被 413 拦截。
+      max-file-size: ${DEBUG_EML_UPLOAD_DEV_MAX_FILE_BYTES:${DEBUG_EML_UPLOAD_MAX_FILE_BYTES:10485760}}
+      max-request-size: ${DEBUG_EML_UPLOAD_DEV_MAX_REQUEST_BYTES:${DEBUG_EML_UPLOAD_MAX_REQUEST_BYTES:12582912}}
 
 source-message:
   original-read:
diff --git a/server/src/main/resources/application-prod.yml b/server/src/main/resources/application-prod.yml
index 79bd2b9..236229a 100644
--- a/server/src/main/resources/application-prod.yml
+++ b/server/src/main/resources/application-prod.yml
@@ -7,6 +7,11 @@ spring:
     driver-class-name: com.mysql.cj.jdbc.Driver
   flyway:
     enabled: true
+  servlet:
+    multipart:
+      # prod Debug EML 如被显式开启，multipart 上限必须先放行到业务文件上限，再由服务层做受控校验。
+      max-file-size: ${DEBUG_EML_UPLOAD_PROD_MAX_FILE_BYTES:${DEBUG_EML_UPLOAD_MAX_FILE_BYTES:10485760}}
+      max-request-size: ${DEBUG_EML_UPLOAD_PROD_MAX_REQUEST_BYTES:${DEBUG_EML_UPLOAD_MAX_REQUEST_BYTES:12582912}}
 
 source-message:
   original-read:
diff --git a/server/src/main/resources/application-test.yml b/server/src/main/resources/application-test.yml
index 9c2b209..73b8c57 100644
--- a/server/src/main/resources/application-test.yml
+++ b/server/src/main/resources/application-test.yml
@@ -7,6 +7,11 @@ spring:
     driver-class-name: com.mysql.cj.jdbc.Driver
   flyway:
     enabled: true
+  servlet:
+    multipart:
+      # test Debug EML multipart 上限必须不小于业务文件上限，避免请求进入 Controller 前被 413 拦截。
+      max-file-size: ${DEBUG_EML_UPLOAD_TEST_MAX_FILE_BYTES:${DEBUG_EML_UPLOAD_MAX_FILE_BYTES:10485760}}
+      max-request-size: ${DEBUG_EML_UPLOAD_TEST_MAX_REQUEST_BYTES:${DEBUG_EML_UPLOAD_MAX_REQUEST_BYTES:12582912}}
 
 source-message:
   original-read:
diff --git a/server/src/main/resources/application.yml b/server/src/main/resources/application.yml
index 72b2094..4f4e15c 100644
--- a/server/src/main/resources/application.yml
+++ b/server/src/main/resources/application.yml
@@ -6,6 +6,11 @@ spring:
     default: dev
   flyway:
     enabled: true
+  servlet:
+    multipart:
+      # Debug EML 默认允许 10MB 文件；request 上限略大于文件上限，给 multipart 边界和字段留空间。
+      max-file-size: ${DEBUG_EML_UPLOAD_MAX_FILE_BYTES:10485760}
+      max-request-size: ${DEBUG_EML_UPLOAD_MAX_REQUEST_BYTES:12582912}
 
 mybatis-plus:
   configuration:
diff --git a/server/src/test/java/cn/nianxx/thhotel/platform/debug/service/DebugEmlMultipartConfigurationTest.java b/server/src/test/java/cn/nianxx/thhotel/platform/debug/service/DebugEmlMultipartConfigurationTest.java
new file mode 100644
index 0000000..d4a5ad6
--- /dev/null
+++ b/server/src/test/java/cn/nianxx/thhotel/platform/debug/service/DebugEmlMultipartConfigurationTest.java
@@ -0,0 +1,32 @@
+package cn.nianxx.thhotel.platform.debug.service;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import cn.nianxx.thhotel.ThHotelApplication;
+import cn.nianxx.thhotel.platform.debug.service.impl.DebugEmlSuperAgentProperties;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.autoconfigure.web.servlet.MultipartProperties;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.test.context.ActiveProfiles;
+
+@SpringBootTest(
+        classes = ThHotelApplication.class,
+        properties = "debug.eml-upload.max-file-bytes=10485760")
+@ActiveProfiles("test")
+class DebugEmlMultipartConfigurationTest {
+
+    @Autowired
+    private MultipartProperties multipartProperties;
+
+    @Autowired
+    private DebugEmlSuperAgentProperties debugEmlProperties;
+
+    @Test
+    void shouldAllowMultipartRequestBeforeDebugEmlBusinessLimit() {
+        assertThat(multipartProperties.getMaxFileSize().toBytes())
+                .isGreaterThanOrEqualTo(debugEmlProperties.getMaxFileBytes());
+        assertThat(multipartProperties.getMaxRequestSize().toBytes())
+                .isGreaterThan(debugEmlProperties.getMaxFileBytes());
+    }
+}