diff --git a/src/plugins/projectexplorer/msvctoolchain.cpp b/src/plugins/projectexplorer/msvctoolchain.cpp
index 406405ee851..4df88de60bd 100644
--- a/src/plugins/projectexplorer/msvctoolchain.cpp
+++ b/src/plugins/projectexplorer/msvctoolchain.cpp
@@ -592,10 +592,10 @@ Macros MsvcToolChain::msvcPredefinedMacros(const QStringList &cxxflags,
 
     QStringList toProcess;
     for (const QString &arg : cxxflags) {
-        if (arg.startsWith(QLatin1String("/D"))) {
+        if (arg.startsWith("/D") || arg.startsWith("-D")) {
             const QString define = arg.mid(2);
             predefinedMacros.append(Macro::fromKeyValue(define));
-        } else if (arg.startsWith(QLatin1String("/U"))) {
+        } else if (arg.startsWith("/U") || arg.startsWith("-U")) {
             predefinedMacros.append(
                 {arg.mid(2).toLocal8Bit(), ProjectExplorer::MacroType::Undefine});
         } else {