Monkey Business is a 1931 American pre-Code comedy film. It is the third of the Marx Brothers' released movies, and the first with an original screenplay rather than an adaptation of one of their Broadway shows. The film also features Thelma Todd, Harry Woods and Ruth Hall. It is directed by Norman Z. McLeod with screenplay by S. J. Perelman and Will B. Johnstone. Much of the story takes place on an ocean liner crossing the Atlantic Ocean.

The Marx Brothers were an American family comedy act that was successful in vaudeville, on Broadway, and in 14 motion pictures from 1905 to 1949. Five of the Marx Brothers' fourteen feature films were selected by the American Film Institute (AFI) as among the top 100 comedy films, with two of them, Duck Soup (1933) and A Night at the Opera (1935), in the top fifteen. They are widely considered by critics, scholars and fans to be among the greatest and most influential comedians of the 20th century. The brothers were included in AFI's 100 Years... 100 Stars list of the 25 greatest male stars of Classical Hollywood cinema, the only performers to be included collectively.