diff --git a/include/wx/html/htmlcell.h b/include/wx/html/htmlcell.h
index 2c99923b80..083ebd8e63 100644
--- a/include/wx/html/htmlcell.h
+++ b/include/wx/html/htmlcell.h
@@ -445,7 +445,7 @@ protected:
 class WXDLLIMPEXP_HTML wxHtmlContainerCell : public wxHtmlCell
 {
 public:
-    wxHtmlContainerCell(wxHtmlContainerCell *parent);
+    explicit wxHtmlContainerCell(wxHtmlContainerCell *parent);
     virtual ~wxHtmlContainerCell();
 
     virtual void Layout(int w) wxOVERRIDE;
diff --git a/interface/wx/html/htmlcell.h b/interface/wx/html/htmlcell.h
index fe17b29ddd..2f64f36556 100644
--- a/interface/wx/html/htmlcell.h
+++ b/interface/wx/html/htmlcell.h
@@ -471,7 +471,7 @@ public:
     /**
         Constructor. @a parent is pointer to parent container or @NULL.
     */
-    wxHtmlContainerCell(wxHtmlContainerCell* parent);
+    explicit wxHtmlContainerCell(wxHtmlContainerCell* parent);
 
     /**
         Detach a child cell.