Cosmas Damian Asam (* 28. September 1686 probably in Benediktbeuern; 10. May 1739 in Munich) was a German painter and architect of the late baroque period. Cosmas Damian Asam worked mainly with his brother, the plasterer and sculptor Egid Quirin Asam.
Asam was a principal master of Southern German ceiling painting between Baroque and Rococo. He worked, partly together with his brother Egid Quirin Asam, on the decoration of the castles in Bruchsal, Ettlingen and Mannheim and the monastery church Weingarten.
For the life and work of the Asam brothers, see Asam brothers.
On Asam's 250th anniversary of death in 1989, the German Federal Post Office issued a commemorative stamp worth 60 pfennigs; it shows Cosmas Damian Asam in front of the ceiling fresco in the Weltenburg monastery church (see picture on the right).