diff --git a/docs/data/data-grid/localization/data.json b/docs/data/data-grid/localization/data.json
index 80986da2a0bd..5e6f16f54e32 100644
--- a/docs/data/data-grid/localization/data.json
+++ b/docs/data/data-grid/localization/data.json
@@ -123,7 +123,7 @@
     "languageTag": "ja-JP",
     "importName": "jaJP",
     "localeName": "Japanese",
-    "missingKeysCount": 25,
+    "missingKeysCount": 0,
     "totalKeysCount": 119,
     "githubLink": "https://github.com/mui/mui-x/blob/master/packages/grid/x-data-grid/src/locales/jaJP.ts"
   },
diff --git a/packages/grid/x-data-grid/src/locales/jaJP.ts b/packages/grid/x-data-grid/src/locales/jaJP.ts
index 62cda421fcb0..dc24c2c86120 100644
--- a/packages/grid/x-data-grid/src/locales/jaJP.ts
+++ b/packages/grid/x-data-grid/src/locales/jaJP.ts
@@ -70,33 +70,33 @@ const jaJPGrid: Partial<GridLocaleText> = {
   filterOperatorIsEmpty: '...空である',
   filterOperatorIsNotEmpty: '...空でない',
   filterOperatorIsAnyOf: '...のいずれか',
-  // 'filterOperator=': '=',
-  // 'filterOperator!=': '!=',
-  // 'filterOperator>': '>',
-  // 'filterOperator>=': '>=',
-  // 'filterOperator<': '<',
-  // 'filterOperator<=': '<=',
+  'filterOperator=': '=',
+  'filterOperator!=': '!=',
+  'filterOperator>': '>',
+  'filterOperator>=': '>=',
+  'filterOperator<': '<',
+  'filterOperator<=': '<=',
 
   // Header filter operators text
-  // headerFilterOperatorContains: 'Contains',
-  // headerFilterOperatorEquals: 'Equals',
-  // headerFilterOperatorStartsWith: 'Starts with',
-  // headerFilterOperatorEndsWith: 'Ends with',
-  // headerFilterOperatorIs: 'Is',
-  // headerFilterOperatorNot: 'Is not',
-  // headerFilterOperatorAfter: 'Is after',
-  // headerFilterOperatorOnOrAfter: 'Is on or after',
-  // headerFilterOperatorBefore: 'Is before',
-  // headerFilterOperatorOnOrBefore: 'Is on or before',
-  // headerFilterOperatorIsEmpty: 'Is empty',
-  // headerFilterOperatorIsNotEmpty: 'Is not empty',
-  // headerFilterOperatorIsAnyOf: 'Is any of',
-  // 'headerFilterOperator=': 'Equals',
-  // 'headerFilterOperator!=': 'Not equals',
-  // 'headerFilterOperator>': 'Greater than',
-  // 'headerFilterOperator>=': 'Greater than or equal to',
-  // 'headerFilterOperator<': 'Less than',
-  // 'headerFilterOperator<=': 'Less than or equal to',
+  headerFilterOperatorContains: '含む',
+  headerFilterOperatorEquals: '等しい',
+  headerFilterOperatorStartsWith: 'で始まる',
+  headerFilterOperatorEndsWith: 'で終わる',
+  headerFilterOperatorIs: 'である',
+  headerFilterOperatorNot: 'ではない',
+  headerFilterOperatorAfter: '...より後ろ',
+  headerFilterOperatorOnOrAfter: '...以降',
+  headerFilterOperatorBefore: '...より前',
+  headerFilterOperatorOnOrBefore: '...以前',
+  headerFilterOperatorIsEmpty: '空白',
+  headerFilterOperatorIsNotEmpty: '空白ではない',
+  headerFilterOperatorIsAnyOf: 'いずれか',
+  'headerFilterOperator=': '等しい',
+  'headerFilterOperator!=': '等しくない',
+  'headerFilterOperator>': 'より大きい',
+  'headerFilterOperator>=': '以上',
+  'headerFilterOperator<': '未満',
+  'headerFilterOperator<=': '以下',
 
   // Filter values text
   filterValueAny: 'いずれか',