diff --git a/NEWS.md b/NEWS.md
index 40b1cd53..4fad9532 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -13,6 +13,7 @@ Red Panda C++ Version 1.0.1
   - fix: expand fold signs on the gutter are not correct
   - enhancement: auto restore mainwindow when open files in one instance
   - fix: the problem & problem set panel can't be correctly , if problem set is enabled
+  - fix: disable code completion doesn't correctly disable project parser
 
 Red Panda C++ Version 1.0.0
   - fix: calculation for code snippets's tab stop positions is not correct
diff --git a/RedPandaIDE/mainwindow.cpp b/RedPandaIDE/mainwindow.cpp
index b8f6c524..ef6629a9 100644
--- a/RedPandaIDE/mainwindow.cpp
+++ b/RedPandaIDE/mainwindow.cpp
@@ -1176,7 +1176,6 @@ void MainWindow::openProject(const QString &filename, bool openFiles)
 
 void MainWindow::changeOptions(const QString &widgetName, const QString &groupName)
 {
-    bool oldCodeCompletion = pSettings->codeCompletion().enabled();
     PSettingsDialog settingsDialog = SettingsDialog::optionDialog();
     if (!groupName.isEmpty()) {
         settingsDialog->setCurrentWidget(widgetName, groupName);
@@ -1188,16 +1187,13 @@ void MainWindow::changeOptions(const QString &widgetName, const QString &groupNa
         return;
     }
 
-    bool newCodeCompletion = pSettings->codeCompletion().enabled();
-    if (!oldCodeCompletion && newCodeCompletion) {
-        Editor *e = mEditorList->getEditor();
-        if (mProject && !e) {
-            scanActiveProject(true);
-        } else if (mProject && e && e->inProject()) {
-            scanActiveProject(true);
-        } else if (e) {
-            e->reparse();
-        }
+    Editor *e = mEditorList->getEditor();
+    if (mProject && !e) {
+        scanActiveProject(true);
+    } else if (mProject && e && e->inProject()) {
+        scanActiveProject(true);
+    } else if (e) {
+        e->reparse();
     }
 
 }
@@ -2015,6 +2011,8 @@ void MainWindow::scanActiveProject(bool parse)
 {
     if (!mProject)
         return;
+    mProject->cppParser()->setEnabled(pSettings->codeCompletion().enabled());
+
     //UpdateClassBrowsing;
     if (parse) {
         resetCppParser(mProject->cppParser(),mProject->options().compilerSet);
diff --git a/RedPandaIDE/parser/cppparser.cpp b/RedPandaIDE/parser/cppparser.cpp
index f7df64c6..5e0e6b73 100644
--- a/RedPandaIDE/parser/cppparser.cpp
+++ b/RedPandaIDE/parser/cppparser.cpp
@@ -699,6 +699,8 @@ QString CppParser::getHeaderFileName(const QString &relativeTo, const QString &l
 
 void CppParser::invalidateFile(const QString &fileName)
 {
+    if (!mEnabled)
+        return;
     {
         QMutexLocker locker(&mMutex);
         if (mParsing || mLockCount>0)
@@ -4806,7 +4808,12 @@ bool CppParser::enabled() const
 
 void CppParser::setEnabled(bool newEnabled)
 {
-    mEnabled = newEnabled;
+    if (mEnabled!=newEnabled) {
+        mEnabled = newEnabled;
+        if (!mEnabled) {
+            this->reset();
+        }
+    }
 }
 
 CppFileParserThread::CppFileParserThread(