Charles Cantor (September 4, 1898 – September 11, 1966) was an American radio and television actor. Cantor was known for his frequent appearances on radio, sometimes, totaling 40 shows a week, during the 1930s, 1940s and 1950s. Cantor also appeared in nearly 30 television shows between 1951 and 1965.

Cantor first stepped onto the radio scene in 1921 as an actor for a local program at WHN in New York City. From there, Cantor's radio career took off. Between the 1930s and the 1950s, Cantor was a feature guest on anywhere between 20 and 40 radio programs a week, most of them comedy shows. Some of his radio guest star appearances included The Shadow, Dick Tracy, The Life of Riley, The Baby Snooks Show and The Kate Smith Hour.

Cantor became popular with radio audiences in 1940 when he joined the cast of The Fred Allen Show. Cantor, along with Alan Reed and John Brown, joined the cast of the new Texaco Star Theater. When "Allen's Alley", a segment in which star Fred Allen would stroll through an imaginary neighborhood conversing with imaginary neighbors, was first introduced in 1942, Cantor soon joined the list of Allen's "neighbors". Cantor portrayed the dim-witted Socrates Mulligan on the Alley.