John F. Cryan (May 6, 1929 – February 6, 2005) was an American Democratic Party politician who served as member of the New Jersey General Assembly and as the Sheriff of Essex County, New Jersey. Cryan was born in Baslick, Castlerea, County Roscommon, and emigrated to the United States in 1948. He served in the U.S. Army during the Korean War. He worked at the Prudential Insurance Company in Newark and as a bus driver with Public Service Transport before opening a tavern in the Vailsburg section of Newark.