diff --git a/src/main.cpp b/src/main.cpp
index a468b24d..cf81a5b8 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -10,6 +10,7 @@
 #include <QDir>
 #include <QSslSocket>
 #include <QOpenGLContext>
+#include <QProcess>
 
 #include "utils/vutils.h"
 #include "vsingleinstanceguard.h"
@@ -233,5 +234,13 @@ int main(int argc, char *argv[])
 
     w.kickOffStartUpTimer(filePaths);
 
-    return app.exec();
+    int ret = app.exec();
+    if (ret == RESTART_EXIT_CODE) {
+        // Ask to restart VNote.
+        guard.exit();
+        QProcess::startDetached(qApp->applicationFilePath(), QStringList());
+        return 0;
+    }
+
+    return ret;
 }
diff --git a/src/vmainwindow.cpp b/src/vmainwindow.cpp
index edfa73cb..7aca8390 100644
--- a/src/vmainwindow.cpp
+++ b/src/vmainwindow.cpp
@@ -1097,6 +1097,12 @@ void VMainWindow::initFileMenu()
 
     fileMenu->addSeparator();
 
+    // Restart.
+    QAction *restartAct = new QAction(tr("Restart"), this);
+    connect(restartAct, &QAction::triggered,
+            this, &VMainWindow::restartVNote);
+    fileMenu->addAction(restartAct);
+
     // Exit.
     QAction *exitAct = new QAction(tr("&Quit"), this);
     exitAct->setToolTip(tr("Quit VNote"));
@@ -3394,3 +3400,8 @@ void VMainWindow::initUpdateTimer()
                 m_noteToolBar->update();
             });
 }
+
+void VMainWindow::restartVNote()
+{
+    QCoreApplication::exit(RESTART_EXIT_CODE);
+}
diff --git a/src/vmainwindow.h b/src/vmainwindow.h
index 0751ed10..ef8ae7c1 100644
--- a/src/vmainwindow.h
+++ b/src/vmainwindow.h
@@ -46,6 +46,8 @@ class VHistoryList;
 class VExplorer;
 class VTagExplorer;
 
+#define RESTART_EXIT_CODE   1000
+
 enum class PanelViewState
 {
     ExpandMode = 0,
@@ -130,6 +132,9 @@ public:
 
     void setCaptainModeEnabled(bool p_enabled);
 
+public slots:
+    void restartVNote();
+
 signals:
     // Emit when editor related configurations were changed by user.
     void editorConfigUpdated();
diff --git a/src/vsingleinstanceguard.cpp b/src/vsingleinstanceguard.cpp
index 42437190..d2a39654 100644
--- a/src/vsingleinstanceguard.cpp
+++ b/src/vsingleinstanceguard.cpp
@@ -7,12 +7,15 @@ const QString VSingleInstanceGuard::c_memKey = "vnote_shared_memory";
 const int VSingleInstanceGuard::c_magic = 133191933;
 
 VSingleInstanceGuard::VSingleInstanceGuard()
-    : m_sharedMemory(c_memKey)
+    : m_sharedMemory(c_memKey),
+      m_online(false)
 {
 }
 
 bool VSingleInstanceGuard::tryRun()
 {
+    m_online = false;
+
     // If we can attach to the sharedmemory, there is another instance running.
     // In Linux, crashes may cause the shared memory segment remains. In this case,
     // this will attach to the old segment, then exit, freeing the old segment.
@@ -31,6 +34,8 @@ bool VSingleInstanceGuard::tryRun()
         str->m_filesBufIdx = 0;
         str->m_askedToShow = false;
         m_sharedMemory.unlock();
+
+        m_online = true;
         return true;
     } else {
         qDebug() << "fail to create shared memory segment";
@@ -109,6 +114,11 @@ bool VSingleInstanceGuard::appendFileToBuffer(SharedStruct *p_str, const QString
 QStringList VSingleInstanceGuard::fetchFilesToOpen()
 {
     QStringList files;
+
+    if (!m_online) {
+        return files;
+    }
+
     Q_ASSERT(m_sharedMemory.isAttached());
     m_sharedMemory.lock();
     SharedStruct *str = (SharedStruct *)m_sharedMemory.data();
@@ -153,15 +163,28 @@ void VSingleInstanceGuard::showInstance()
 
 bool VSingleInstanceGuard::fetchAskedToShow()
 {
-    bool ret = false;
+    if (!m_online) {
+        return false;
+    }
 
     Q_ASSERT(m_sharedMemory.isAttached());
     m_sharedMemory.lock();
     SharedStruct *str = (SharedStruct *)m_sharedMemory.data();
     Q_ASSERT(str->m_magic == c_magic);
-    ret = str->m_askedToShow;
+    bool ret = str->m_askedToShow;
     str->m_askedToShow = false;
     m_sharedMemory.unlock();
 
     return ret;
 }
+
+void VSingleInstanceGuard::exit()
+{
+    if (!m_online) {
+        return;
+    }
+
+    Q_ASSERT(m_sharedMemory.isAttached());
+    m_sharedMemory.detach();
+    m_online = false;
+}
diff --git a/src/vsingleinstanceguard.h b/src/vsingleinstanceguard.h
index 750f3a3a..f212aeaf 100644
--- a/src/vsingleinstanceguard.h
+++ b/src/vsingleinstanceguard.h
@@ -28,6 +28,9 @@ public:
     // Whether this instance is asked to show itself.
     bool fetchAskedToShow();
 
+    // A running instance requests to exit.
+    void exit();
+
 private:
     // The count of the entries in the buffer to hold the path of the files to open.
     enum { FilesBufCount = 1024 };
@@ -53,6 +56,8 @@ private:
     // Returns true if succeeds or false if there is no enough space.
     bool appendFileToBuffer(SharedStruct *p_str, const QString &p_file);
 
+    bool m_online;
+
     QSharedMemory m_sharedMemory;
 
     static const QString c_memKey;