Walter Leighton Clark (1859–1935) was an American businessman, inventor, artist, and philanthropist based in Stockbridge, Massachusetts and New York City.

Together with sculptor Daniel Chester French and Dr. Austen Fox Riggs,[1] Clark also played a central role in the founding of the Berkshire Theatre Festival in Stockbridge, Massachusetts.

When the Stockbridge Casino, designed by Stanford White in 1887, fell into disuse, Clark, French, and Riggs purchased the building and had it moved to its current location.

During his time in Stockbridge he also studied sculpture with Daniel Chester French, and in 1916 acted as pallbearer for the funeral of Alexander Wilson Drake.

A clipping from The Berkshire Eagle lists other items sold as English and American period furniture, a number of important family pieces, copper and brassware, and 38 paintings.