Harry Conway "Bud" Fisher (April 3, 1885 – September 7, 1954) was an American cartoonist who created the first successful daily comic strip in the United States.

Born in Chicago, Illinois, Fisher studied at the University of Chicago and then went to work as a journalist and sketch artist in the sports department of the San Francisco Chronicle. In late 1907, he introduced a comic strip character named Mr. A. Mutt (the initial stood for Augustus) that became instantly popular with readers. In March 1908, Fisher added a second character, the diminutive Jeff, the opposite of the tall and skinny Mutt. The Mutt and Jeff comic strip gained such popularity that Fisher, who was able to claim copyright to the characters, received an offer to produce it for the San Francisco Examiner, owned by William Randolph Hearst. The move to the Hearst Corporation chain exposed the strip to a multitude of new readers across the United States.

In 1911, Nestor Studios of New Jersey acquired the right to make Mutt and Jeff short film comedies, after which Fisher decided he could make more money controlling film production himself. In 1913, he created the Bud Fisher Film Corporation and signed a deal with American Pathé. They made 36 Mutt and Jeff short comedies in 1913, but production ceased for two years when Fisher's copyright was challenged. Once the courts upheld Fisher's copyright claim, the comic strip was syndicated nationwide, and between 1916 and 1926, his film production company created another 277 Mutt and Jeff film productions. On these film projects, Fisher is almost exclusively credited as the writer, animator and director, although the majority of animation was by Raoul Barré and Charles Bowers.

Mutt and Jeff was also published in comic book form. The income from the multiple uses of his characters made Fisher a wealthy man. In 1932, he authorized Al Smith to produce the strip under his supervision. Smith drew Mutt and Jeff for 48 years. When Fisher died in 1954, Smith began signing his own name and continued to draw the strip until 1980 when George Breisacher took over for its final two years.

Fisher acquired a large stable of Thoroughbred race horses. In 1924, his horse Nellie Morse became the fourth filly (out of only five total as of 2009) to win the Preakness Stakes. That same year, his colt Mr. Mutt finished second in the Belmont Stakes.

Bud Fisher died at the age of 69 in New York City and was buried in the Woodlawn Cemetery in The Bronx.