A sloppy joe is a sandwich consisting of ground beef or pork, onions, tomato sauce or ketchup, Worcestershire sauce, and other seasonings, served on a hamburger bun. The dish originated in the United States during the early 20th century.

Several variations of the sloppy joe exist in North America. In Quebec, Canada, sandwiches of stewed ground beef such as pain à la viande and pain fourré gumbo are usually served on hot dog buns. A similar sandwich, the "dynamite", exists in the area around Woonsocket, Rhode Island, and is distinguished by the use of onions, bell peppers, and sometimes celery.

Stewed meat sandwiches are common in several other culinary traditions as well. The rou jia mo, from China's Shaanxi Province, consists of stewed pork, beef, or lamb on a steamed bun. Keema pav of Indian cuisine uses a pav bread roll filled with keema, a minced, stewed, curried meat.

Ground turkey or textured vegetable protein may be used as a substitute for ground beef.

A sloppy joe differs from a traditional loose meat or tavern sandwich due largely to its tomato-based sauce.

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