diff --git a/xarray/plot/plot.py b/xarray/plot/plot.py
index f0cf356fc5d..5911a24e29a 100644
--- a/xarray/plot/plot.py
+++ b/xarray/plot/plot.py
@@ -606,8 +606,7 @@ def newplotfunc(darray, x=None, y=None, figsize=None, size=None,
             cbar = _add_colorbar(primitive, ax, cbar_ax, cbar_kwargs,
                                  cmap_params)
 
-        elif (cbar_ax is not None
-              or (cbar_kwargs is not None and cbar_kwargs != {})):
+        elif (cbar_ax is not None or cbar_kwargs):
             # inform the user about keywords which aren't used
             raise ValueError("cbar_ax and cbar_kwargs can't be used with "
                              "add_colorbar=False.")