diff --git a/.eslintrc.js b/.eslintrc.js
index c65b1c31fb..4e59b55aaf 100644
--- a/.eslintrc.js
+++ b/.eslintrc.js
@@ -212,6 +212,7 @@ const config = {
     'unicorn/prefer-dom-node-remove': 'error',
     'unicorn/prefer-array-some': 'error',
     'unicorn/prefer-date-now': 'error',
+    'unicorn/no-typeof-undefined': 'error',
     'unicorn/no-useless-promise-resolve-reject': 'error',
     'sonarjs/no-all-duplicated-branches': 'error',
     'sonarjs/no-element-overwrite': 'error',
diff --git a/packages/backend/server/src/config/def.ts b/packages/backend/server/src/config/def.ts
index 895df5f08d..1b9a065d9a 100644
--- a/packages/backend/server/src/config/def.ts
+++ b/packages/backend/server/src/config/def.ts
@@ -50,7 +50,7 @@ function boolean(value: string) {
 }
 
 export function parseEnvValue(value: string | undefined, type?: EnvConfigType) {
-  if (typeof value === 'undefined') {
+  if (value === undefined) {
     return;
   }
 
diff --git a/packages/backend/server/src/config/env.ts b/packages/backend/server/src/config/env.ts
index f68dfedd5f..8d5b950fff 100644
--- a/packages/backend/server/src/config/env.ts
+++ b/packages/backend/server/src/config/env.ts
@@ -10,7 +10,7 @@ export function applyEnvToConfig(rawConfig: AFFiNEConfig) {
         ? [config, process.env[env]]
         : [config[0], parseEnvValue(process.env[env], config[1])];
 
-    if (typeof value !== 'undefined') {
+    if (value !== undefined) {
       set(rawConfig, path, value);
     }
   }