James Thomas Callahan (October 4, 1930 – August 3, 2007) was an American film and television actor who appeared in more than 120 films and television programs between 1959 and 2007. He is perhaps best known for his portrayal from 1987 to 1990 of Walter Powell on the syndicated sitcom Charles in Charge, starring Scott Baio.

He also had recurring roles in two 1960s series, as Danny Adams in ABC's Wendy and Me, with a cast including George Burns, Connie Stevens, Ron Harper, and J. Pat O'Malley, and as Lieutenant O'Connell on NBC's 13-episode war drama, Convoy, with John Gavin and John Larch.