Joseph "Joe" William Kelly (born June 9, 1988) is an American professional baseball pitcher for the Boston Red Sox. He has served as both a starter and reliever. His repertoire features a power sinker that can reach speeds of up to 96 miles per hour (MPH).

Kelly has also gained publicity for his comical repertoire, such as skillfully dancing in the outfield during practice, disguising himself while interviewing the unwitting rapper Nelly, and engaging in lengthy staredown with Los Angeles Dodgers outfielder Scott Van Slyke before a 2013 National League Championship Series game.