diff --git a/Source/Core/DolphinWX/ISOProperties.cpp b/Source/Core/DolphinWX/ISOProperties.cpp
index 0be1535f09..8479b6eb6d 100644
--- a/Source/Core/DolphinWX/ISOProperties.cpp
+++ b/Source/Core/DolphinWX/ISOProperties.cpp
@@ -99,7 +99,7 @@ BEGIN_EVENT_TABLE(CISOProperties, wxDialog)
 	EVT_CHOICE(ID_LANG, CISOProperties::OnChangeBannerLang)
 END_EVENT_TABLE()
 
-CISOProperties::CISOProperties(const std::string fileName, wxWindow* parent, wxWindowID id, const wxString& title, const wxPoint& position, const wxSize& size, long style)
+CISOProperties::CISOProperties(const std::string& fileName, wxWindow* parent, wxWindowID id, const wxString& title, const wxPoint& position, const wxSize& size, long style)
 	: wxDialog(parent, id, title, position, size, style)
 {
 	// Load ISO data
diff --git a/Source/Core/DolphinWX/ISOProperties.h b/Source/Core/DolphinWX/ISOProperties.h
index 2f07ec8c10..fff7ba3352 100644
--- a/Source/Core/DolphinWX/ISOProperties.h
+++ b/Source/Core/DolphinWX/ISOProperties.h
@@ -51,7 +51,7 @@ struct PHackData
 class CISOProperties : public wxDialog
 {
 public:
-	CISOProperties(const std::string fileName,
+	CISOProperties(const std::string& fileName,
 			wxWindow* parent,
 			wxWindowID id = wxID_ANY,
 			const wxString& title = _("Properties"),