diff --git a/engines/macventure/controls.cpp b/engines/macventure/controls.cpp
index 26807a33089..898ddac8e83 100644
--- a/engines/macventure/controls.cpp
+++ b/engines/macventure/controls.cpp
@@ -24,7 +24,7 @@
 
 namespace MacVenture {
 CommandButton::CommandButton() {
-	_gui = nullptr;
+	_gui = NULL;
 }
 
 CommandButton::CommandButton(ControlData data, Gui *g) {
diff --git a/engines/macventure/datafiles.cpp b/engines/macventure/datafiles.cpp
index 77ecaee6263..496fa919c88 100644
--- a/engines/macventure/datafiles.cpp
+++ b/engines/macventure/datafiles.cpp
@@ -74,7 +74,7 @@ Common::SeekableReadStream *MacVentureEngine::getBorderFile(MVWindowType windowT
 	filename += (isActive ? "_act.bmp" : "_inac.bmp");
 	if (!_dataBundle->hasFile(filename)) {
 		warning("Missing border file '%s' in data bundle", filename.c_str());
-		return nullptr;
+		return NULL;
 	}
 
 	return _dataBundle->createReadStreamForMember(filename);
diff --git a/engines/macventure/gui.cpp b/engines/macventure/gui.cpp
index 56381369bba..65b11ee4029 100644
--- a/engines/macventure/gui.cpp
+++ b/engines/macventure/gui.cpp
@@ -103,11 +103,11 @@ void menuCommandsCallback(int action, Common::String &text, void *data);
 Gui::Gui(MacVentureEngine *engine, Common::MacResManager *resman) {
 	_engine = engine;
 	_resourceManager = resman;
-	_windowData = nullptr;
-	_controlData = nullptr;
+	_windowData = NULL;
+	_controlData = NULL;
 	_draggedObj.id = 0;
 	_draggedObj.pos = Common::Point(0, 0);
-	_dialog = nullptr;
+	_dialog = NULL;
 
 	_cursor = new Cursor(this);
 
@@ -846,7 +846,7 @@ void Gui::showPrebuiltDialog(PrebuiltDialogs type) {
 }
 
 bool Gui::isDialogOpen() {
-	return _dialog != nullptr;
+	return _dialog != NULL;
 }
 
 void Gui::setTextInput(Common::String str) {
@@ -856,7 +856,7 @@ void Gui::setTextInput(Common::String str) {
 
 void Gui::closeDialog() {
 	delete _dialog;
-	_dialog = nullptr;
+	_dialog = NULL;
 }
 
 void Gui::getTextFromUser() {
@@ -950,7 +950,7 @@ Graphics::MacWindow * Gui::findWindow(WindowReference reference) {
 	}
 	switch (reference) {
 	case MacVenture::kNoWindow:
-		return nullptr;
+		return NULL;
 	case MacVenture::kCommandsWindow:
 		return _controlsWindow;
 	case MacVenture::kMainGameWindow:
@@ -964,7 +964,7 @@ Graphics::MacWindow * Gui::findWindow(WindowReference reference) {
 	case MacVenture::kDiplomaWindow:
 		return _diplomaWindow;
 	}
-	return nullptr;
+	return NULL;
 }
 
 void Gui::ensureInventoryOpen(WindowReference reference, ObjID id) {
diff --git a/engines/macventure/sound.cpp b/engines/macventure/sound.cpp
index f05c88fcd66..455a1916ac5 100644
--- a/engines/macventure/sound.cpp
+++ b/engines/macventure/sound.cpp
@@ -30,7 +30,7 @@ namespace MacVenture {
 
 // SoundManager
 SoundManager::SoundManager(MacVentureEngine *engine, Audio::Mixer *mixer) {
-	_container = nullptr;
+	_container = NULL;
 	Common::String filename = engine->getFilePath(kSoundPathID);
 	_container = new Container(filename);
 	_mixer = mixer;