Isadore Bernstein (November 26, 1876 – October 19, 1944) was an American screenwriter. He wrote screenplays for 65 films between 1914 and 1938. He was born in New York, New York and died in Hollywood, California from a heart attack.
Bernstein was the West Coast studio manager for Carl Laemmle. Although he acted as Laemmle's representative concerning many business issues, he was not a principal as was Pat Powers in the formation of Universal Film Manufacturing Company (Universal Pictures).