Donald Alan Diamond (Brooklyn, Nova York, 4 de juny de 1921 - Los Angeles, Califòrnia, 19 de juny de 2011) va ser un actor de ràdio, cinema i televisió nord-americà.

Brooklyn-born Don Diamond's most famous role is probably that of the scheming and ambitious, but inept and somewhat cowardly, underling Crazy Cat to Frank DeKova's Chief Wild Eagle in the cult western comedy series F Troop (1965). By the time he got that role he had been an actor for quite some time, starting out in radio in the early 1940s, where he discovered that he had a knack for picking up dialects, especially Spanish. He became so proficient in it that many believed he was actually Spanish or Mexican, when in reality his family came from Russia. His facility in that dialect got him the role as the Mexican sidekick of Kit Carson in the early TV series The Adventures of Kit Carson (1951). He also landed a recurring part as a Spanish corporal in the Disney TV series Zorro (1957). In addition to his TV and film work, he did much voice-over work in both cartoons and commercials.