Bayan-Öndör (, , Mongolian: rich plateau, , ) may refer to:

Mongolia several Sums (districts) in different Aimags (provinces), Mongolia Bayan-Öndör, Bayankhongor Bayan-Öndör, Orkhon Bayan-Öndör, Övörkhangai

China , a sum (Township) in Ar Horqin Banner, Inner Mongolia