diff --git a/src/plugins/designer/cpp/newclasswidget.cpp b/src/plugins/designer/cpp/newclasswidget.cpp
index 89a9f78546b..2f42e743226 100644
--- a/src/plugins/designer/cpp/newclasswidget.cpp
+++ b/src/plugins/designer/cpp/newclasswidget.cpp
@@ -73,6 +73,7 @@ NewClassWidget::NewClassWidget(QWidget *parent) :
     d->m_ui.classTypeLabel->setVisible(false);
     d->m_ui.classTypeComboBox->setVisible(false);
 
+    d->m_ui.classLineEdit->setNamespacesEnabled(true);
     setNamesDelimiter(QLatin1String("::"));
 
     connect(d->m_ui.classLineEdit, &Utils::ClassNameValidatingLineEdit::updateFileName,