Andrew Allan Clyde (March 25, 1892 – May 18, 1967), known professionally as Andy Clyde, was a Scottish-born American film and television actor whose career spanned some 45 years. In 1921 he broke into silent films as a Mack Sennett comic, debuting in On a Summer Day. He was the fifth of six children of theatrical actor, producer and manager John Clyde. Clyde's brother David and his sister Jean also became screen actors.

Clyde may be best known for his work as California Carlson in the Hopalong Cassidy movie series, as well as for starring in 79 comedy shorts for Columbia Pictures from 1934-1956. He is also known for recurring roles in two television series: the farmer Cully Wilson in CBS's Lassie and as the neighbor George MacMichael on ABC's The Real McCoys.

At age 19 Clyde toured Scotland with Durward Lely & Company, playing Connor Martin in the romantic Irish musical costume drama The Wearin’ o’ the Green. In 1912, Clyde first came to the United States on tour in the Graham Moffat Players, playing the part of Bob Dewar in a vaudeville comedy sketch depicting tenement life in Glasgow called The Concealed Bed. Years later, at the invitation of his close friend James Finlayson, he returned to the United States in 1920 to join producer Mack Sennett's roster of comedians.

Clyde's mastery of makeup allowed him tremendous versatility; he could play everything from grubby young guttersnipes to old crackpot scientists. He hit upon an "old man" characterization in his short comedies, and it was immediately successful. Adopting a gray wig and mustache, he used this makeup for the rest of his short-subject career, and the character was so durable that he literally grew into it. He starred in short comedies longer than any other actor (32 years, 1924–56).

He made a successful transition to sound films while working for Sennett. In 1932, when the Sennett studio was facing financial problems, Sennett cut Clyde's salary. Clyde objected and left the studio. Sennett then put the "old man" costume on character actor Irving Bacon. Audiences saw through the masquerade, and Sennett abandoned the character. Educational Pictures, Sennett's distributor, took over the Andy Clyde series, which continued for two more years.

Columbia Pictures launched its short subject department in 1934 and Clyde was one of the first comedy stars signed by producer Jules White. Unlike many of the Columbia short-subject comedians who indulged in broad facial and physical gestures, Clyde was subtler and more economical: his comic timing was so good that he could merely lift an eyebrow, shudder slightly, or mutter "My, my, my" for humorous effect.

Clyde also kept busy as a character actor in feature films. He almost always appeared as a supporting actor: for example, he played a sad provincial constable in the Katharine Hepburn film The Little Minister and Charles Coburn's drinking buddy in The Green Years. He did play a couple of leads for low-budget, independent producers: the comedy Red Lights Ahead (1935) and the western Sundown Riders (1944).

By the 1940s, Clyde had been gravitating toward outdoor and Western adventures. Clyde is well remembered for his roles as a comic sidekick. He was most often associated with William Boyd in the Hopalong Cassidy series, as "California Carlson" (a role he also played in the Hopalong Cassidy radio program. He stayed with the Cassidy feature films until the series lapsed in 1948. Clyde also worked on the Hopalong Cassidy "record readers" issued by Capitol Records in the 1950s. Clyde's home studio, Columbia, cast Clyde prominently in feature-length musical westerns of the mid-1940s.