diff --git a/frontend/src/components/QueryEditor.external-sql-save.test.tsx b/frontend/src/components/QueryEditor.external-sql-save.test.tsx
index 1f2371d2..efcac9de 100644
--- a/frontend/src/components/QueryEditor.external-sql-save.test.tsx
+++ b/frontend/src/components/QueryEditor.external-sql-save.test.tsx
@@ -170,6 +170,7 @@ const autoFetchState = vi.hoisted(() => ({
 
 const monacoEditorMockState = vi.hoisted(() => ({
   deferOnMount: false,
+  latestProps: null as any,
 }));
 
 const defaultEditorContributionResolver = (state: {
@@ -199,7 +200,9 @@ const editorState = vi.hoisted(() => {
     position: { lineNumber: 1, column: 1 },
     selection: null as any,
     providers: [] as any[],
+    providerLanguages: [] as string[],
     hoverProviders: [] as any[],
+    hoverProviderLanguages: [] as string[],
     contentChangeListeners: [] as Array<() => void>,
     cursorPositionListeners: [] as Array<(event: any) => void>,
     modelContentListeners: [] as Array<(event: any) => void>,
@@ -365,7 +368,9 @@ vi.mock('../utils/autoFetchVisibility', () => ({
 }));
 
 vi.mock('@monaco-editor/react', () => ({
-  default: ({ defaultValue, onChange, onMount }: any) => {
+  default: (props: any) => {
+    const { defaultValue, onChange, onMount } = props;
+    monacoEditorMockState.latestProps = props;
     React.useEffect(() => {
       editorState.value = String(defaultValue || '');
       editorState.latestOnChange = onChange;
@@ -376,11 +381,13 @@ vi.mock('@monaco-editor/react', () => ({
         languages: {
           CompletionItemKind: { Keyword: 1, Function: 2, Field: 3 },
           CompletionItemInsertTextRule: { InsertAsSnippet: 1 },
-          registerCompletionItemProvider: vi.fn((_language: string, provider: any) => {
+          registerCompletionItemProvider: vi.fn((language: string, provider: any) => {
+            editorState.providerLanguages.push(language);
             editorState.providers.push(provider);
             return { dispose: vi.fn() };
           }),
-          registerHoverProvider: vi.fn((_language: string, provider: any) => {
+          registerHoverProvider: vi.fn((language: string, provider: any) => {
+            editorState.hoverProviderLanguages.push(language);
             editorState.hoverProviders.push(provider);
             return { dispose: vi.fn() };
           }),
@@ -865,9 +872,12 @@ describe('QueryEditor external SQL save', () => {
     editorState.value = '';
     editorState.position = { lineNumber: 1, column: 1 };
     editorState.selection = null;
+    monacoEditorMockState.latestProps = null;
     editorState.domNode.style.cursor = '';
     editorState.providers = [];
+    editorState.providerLanguages = [];
     editorState.hoverProviders = [];
+    editorState.hoverProviderLanguages = [];
     editorState.contentChangeListeners = [];
     editorState.cursorPositionListeners = [];
     editorState.modelContentListeners = [];
@@ -2369,9 +2379,34 @@ describe('QueryEditor external SQL save', () => {
 
     const completionState = (globalThis as any).__gonaviSqlCompletionState;
 
-    expect(editorState.hoverProviders).toHaveLength(1);
-    expect(editorState.providers).toHaveLength(3);
-    expect(completionState.disposables).toHaveLength(4);
+    expect(editorState.hoverProviderLanguages).toEqual(['sql', 'mysql']);
+    expect(editorState.providerLanguages).toEqual(['sql', 'mysql', 'sql', 'mysql', 'sql', 'mysql']);
+    expect(editorState.hoverProviders).toHaveLength(2);
+    expect(editorState.providers).toHaveLength(6);
+    expect(completionState.disposables).toHaveLength(8);
+
+    await act(async () => {
+      renderer.unmount();
+    });
+  });
+
+  it.each([
+    ['mysql', 'mysql'],
+    ['mariadb', 'mysql'],
+    ['postgres', 'sql'],
+  ])('uses the %s connection grammar before formatting SQL', async (dbType, expectedLanguage) => {
+    storeState.connections[0].config.type = dbType;
+    const initialSql = "update finan_ set openid = 'ol_' where pay_status = '0' limit 50";
+
+    let renderer!: ReactTestRenderer;
+    await act(async () => {
+      renderer = create(<QueryEditor tab={createTab({ query: initialSql })} />);
+    });
+
+    expect(monacoEditorMockState.latestProps).toMatchObject({
+      defaultValue: initialSql,
+      language: expectedLanguage,
+    });
 
     await act(async () => {
       renderer.unmount();
@@ -6122,7 +6157,7 @@ describe('QueryEditor external SQL save', () => {
       await Promise.resolve();
     });
 
-    expect(editorState.hoverProviders).toHaveLength(1);
+    expect(editorState.hoverProviders).toHaveLength(2);
     const hover = editorState.hoverProviders[0].provideHover(
       editorState.editor.getModel(),
       { lineNumber: 1, column: 18 },
diff --git a/frontend/src/components/QueryEditor.tsx b/frontend/src/components/QueryEditor.tsx
index 96a9acf5..4ae07b3b 100644
--- a/frontend/src/components/QueryEditor.tsx
+++ b/frontend/src/components/QueryEditor.tsx
@@ -160,6 +160,7 @@ import {
     resolveOracleLikeExecutionSchemaName,
     resolveOracleLikeLookupSchemaCandidates,
     resolveQueryEditorFormatterLanguage,
+    resolveQueryEditorMonacoLanguage,
     resolveQueryEditorHoverTarget,
     resolveQueryEditorNavigationDecorations,
     resolveQueryEditorNavigationTarget,
@@ -886,7 +887,8 @@ const resolveQueryEditorAiConnectionHost = (connection: any): string => {
 
 // HMR 重载时释放旧注册避免补全和 hover 内容重复
 const _g = globalThis as any;
-const SQL_COMPLETION_PROVIDER_VERSION = '20260715-oracle-view-synonym-v1';
+const SQL_COMPLETION_PROVIDER_VERSION = '20260718-mysql-language-v1';
+const QUERY_EDITOR_MONACO_LANGUAGE_IDS = ['sql', 'mysql'] as const;
 if (!_g.__gonaviSqlCompletionState) {
     _g.__gonaviSqlCompletionState = { registered: false, version: '', disposables: [] as any[] };
 }
@@ -1379,6 +1381,12 @@ const QueryEditor: React.FC<{ tab: TabData; isActive?: boolean }> = ({ tab, isAc
       ),
       [connections, currentConnectionId],
   );
+  const queryEditorMonacoLanguage = useMemo(
+      () => resolveQueryEditorMonacoLanguage(
+          connections.find(connection => connection.id === currentConnectionId),
+      ),
+      [connections, currentConnectionId],
+  );
 
   const addSqlLog = useStore(state => state.addSqlLog);
   const sqlLogCount = useStore(state => state.sqlLogs.length);
@@ -4860,7 +4868,17 @@ const QueryEditor: React.FC<{ tab: TabData; isActive?: boolean }> = ({ tab, isAc
       _g.__gonaviSqlCompletionState.version = SQL_COMPLETION_PROVIDER_VERSION;
       sqlCompletionDisposables.forEach((d: any) => d?.dispose?.());
       sqlCompletionDisposables.length = 0;
-      sqlCompletionDisposables.push(monaco.languages.registerHoverProvider('sql', {
+      const registerQueryEditorHoverProvider = (provider: any) => {
+          QUERY_EDITOR_MONACO_LANGUAGE_IDS.forEach((languageId) => {
+              sqlCompletionDisposables.push(monaco.languages.registerHoverProvider(languageId, provider));
+          });
+      };
+      const registerQueryEditorCompletionProvider = (provider: any) => {
+          QUERY_EDITOR_MONACO_LANGUAGE_IDS.forEach((languageId) => {
+              sqlCompletionDisposables.push(monaco.languages.registerCompletionItemProvider(languageId, provider));
+          });
+      };
+      registerQueryEditorHoverProvider({
           provideHover: (model: any, position: any) => {
               const normalizedPosition = normalizeEditorPosition(position);
               if (!normalizedPosition) {
@@ -4896,8 +4914,8 @@ const QueryEditor: React.FC<{ tab: TabData; isActive?: boolean }> = ({ tab, isAc
                   contents: [{ value: buildQueryEditorHoverMarkdown(hoverTarget) }],
               };
           },
-      }));
-      sqlCompletionDisposables.push(monaco.languages.registerCompletionItemProvider('sql', {
+      });
+      registerQueryEditorCompletionProvider({
           triggerCharacters: ['.'],
           provideCompletionItems: async (model: any, position: any, _context?: any, token?: { isCancellationRequested?: boolean }) => {
               if (isSqlCompletionRequestCancelled(token)) {
@@ -5792,8 +5810,8 @@ const QueryEditor: React.FC<{ tab: TabData; isActive?: boolean }> = ({ tab, isAc
                   ];
               return { suggestions };
           }
-      }));
-      sqlCompletionDisposables.push(monaco.languages.registerCompletionItemProvider('sql', {
+      });
+      registerQueryEditorCompletionProvider({
           triggerCharacters: ['/'],
           provideCompletionItems: (model: any, position: any) => {
               const lineContent = model.getLineContent(position.lineNumber);
@@ -5820,11 +5838,11 @@ const QueryEditor: React.FC<{ tab: TabData; isActive?: boolean }> = ({ tab, isAc
                   })),
               };
           },
-      }));
+      });
 
 
       // SQL snippet completion provider
-      sqlCompletionDisposables.push(monaco.languages.registerCompletionItemProvider('sql', {
+      registerQueryEditorCompletionProvider({
           provideCompletionItems: (model: any, position: any) => {
               const word = model.getWordUntilPosition(position);
               const prefix = word.word.toLowerCase();
@@ -5856,7 +5874,7 @@ const QueryEditor: React.FC<{ tab: TabData; isActive?: boolean }> = ({ tab, isAc
                   })),
               };
           },
-      }));
+      });
 
       } // end sqlCompletionRegistered guard
 
@@ -8710,7 +8728,7 @@ const QueryEditor: React.FC<{ tab: TabData; isActive?: boolean }> = ({ tab, isAc
           <Editor 
             height="100%" 
             gonaviTypography="code"
-            defaultLanguage="sql" 
+            language={queryEditorMonacoLanguage}
             theme={darkMode ? "transparent-dark" : "transparent-light"}
             defaultValue={query}
             onChange={(val) => {
diff --git a/frontend/src/components/queryEditor/QueryEditorHelpers.test.ts b/frontend/src/components/queryEditor/QueryEditorHelpers.test.ts
index 234fac21..983cae1b 100644
--- a/frontend/src/components/queryEditor/QueryEditorHelpers.test.ts
+++ b/frontend/src/components/queryEditor/QueryEditorHelpers.test.ts
@@ -7,11 +7,25 @@ import {
     resolveOracleLikeDefaultSchemaName,
     resolveOracleLikeExecutionSchemaName,
     resolveOracleLikeLookupSchemaCandidates,
+    resolveQueryEditorMonacoLanguage,
     resolveQueryEditorNavigationTarget,
     selectUnqualifiedCompletionSynonyms,
     shouldHandleQueryEditorRunShortcutFallback,
 } from './QueryEditorHelpers';
 
+describe('QueryEditor Monaco SQL grammar', () => {
+    it.each([
+        [{ config: { type: 'mysql' } }, 'mysql'],
+        [{ config: { type: 'mariadb' } }, 'mysql'],
+        [{ config: { type: 'custom', driver: 'greatdb' } }, 'mysql'],
+        [{ config: { type: 'oceanbase', oceanBaseProtocol: 'mysql' } }, 'mysql'],
+        [{ config: { type: 'oceanbase', oceanBaseProtocol: 'oracle' } }, 'sql'],
+        [{ config: { type: 'postgres' } }, 'sql'],
+    ])('maps connection row %# to the expected Monaco grammar', (connection, expectedLanguage) => {
+        expect(resolveQueryEditorMonacoLanguage(connection)).toBe(expectedLanguage);
+    });
+});
+
 describe('QueryEditor run shortcut routing', () => {
     it('reserves editor-originated shortcuts for Monaco and keeps document targets as a fallback', () => {
         const editorTarget = {} as Node;
diff --git a/frontend/src/components/queryEditor/QueryEditorHelpers.ts b/frontend/src/components/queryEditor/QueryEditorHelpers.ts
index 7a2635a6..6a14503f 100644
--- a/frontend/src/components/queryEditor/QueryEditorHelpers.ts
+++ b/frontend/src/components/queryEditor/QueryEditorHelpers.ts
@@ -2,7 +2,7 @@ import type { SqlLanguage } from 'sql-formatter';
 import type { TabData, ColumnDefinition, IndexDefinition } from '../../types';
 import { DBGetColumns, DBGetIndexes, DBQuery } from '../../../wailsjs/go/app/App';
 import { buildRpcConnectionConfig } from '../../utils/connectionRpcConfig';
-import { isOracleLikeDialect, resolveSqlDialect } from '../../utils/sqlDialect';
+import { isMysqlFamilyDialect, isOracleLikeDialect, resolveSqlDialect } from '../../utils/sqlDialect';
 import { extractQueryResultTableRef, type QueryResultTableRef } from '../../utils/queryResultTable';
 import { quoteIdentPart } from '../../utils/sql';
 import { splitSidebarQualifiedName } from '../../utils/sidebarLocate';
@@ -572,6 +572,17 @@ export const normalizeMetadataDialect = (conn: any): string => {
     return String(dialect || '').toLowerCase();
 };
 
+export type QueryEditorMonacoLanguage = 'sql' | 'mysql';
+
+export const resolveQueryEditorMonacoLanguage = (conn: any): QueryEditorMonacoLanguage => {
+    const dialect = resolveSqlDialect(
+        String(conn?.config?.type || ''),
+        String(conn?.config?.driver || ''),
+        { oceanBaseProtocol: conn?.config?.oceanBaseProtocol },
+    );
+    return isMysqlFamilyDialect(dialect) ? 'mysql' : 'sql';
+};
+
 export const resolveQueryEditorFormatterLanguage = (conn: any): SqlLanguage => {
     const dialect = normalizeMetadataDialect(conn);
     switch (dialect) {