Ralph Clifford Lynn (8 March 1882 – 8 August 1962) was an English actor who had a 60-year career, and is best remembered for playing comedy parts in the Aldwych farces first on stage and then in film.

Lynn became an actor at the age of 18 and very soon began to be cast in knut or "silly ass" roles. He played such parts as a supporting actor for more than two decades until 1922, when he was cast in the lead of a new West End farce, Tons of Money, in which he achieved immediate stardom. After the success of this play, its co-producer, the actor-manager Tom Walls, leased the Aldwych Theatre in London, where for the next ten years he and Lynn co-starred in a series of successful farces, most of which were written for them by Ben Travers.

Many of the Aldwych farces were made into films starring Lynn and Walls, and the two were ranked among the most popular British film actors of the 1930s. He continued his stage career during and after the Second World War, scoring another hit in London and on tour with Is your Honeymoon Really Necessary? (1944). He continued to play in both new works by Travers and others, and in revivals of his earlier successes, and made his last London appearance in 1958.

Lynn was born in Salford, Lancashire, the son of Gordon James Lynn, an insurance manager, and his wife, Janet née Thomas.

In 1900 Lynn made his stage debut at Wigan in The King of Terrors. He spent his first 14 years as an actor performing in the British provinces and in the United States; he appeared at the Colonial Theatre, New York, in May 1913, as Algy Slowman in a revival of The Purple Lady. He made his first appearance on the London stage at the Empire Theatre in October 1914, as Montague Mayfair in By Jingo, If We Do—!, a revue by Arthur Wimperis and Hartley Carrick with music by Herman Finck. The Observer said of him, "We have not, to our knowledge, seen Mr. Ralph Lynn before; but Mr. Lynn is a deceptive player. To begin with, you think he is going to be merely the usual '[k]nut'. As the piece goes on he proves himself a true comedian."

In 1920 Lynn married the actress Gladys Miles; they had a son and a daughter. He continued his theatre career in mostly "silly ass" supporting roles, in London and in the provinces, until he achieved stardom in 1922, when Leslie Henson and Tom Walls cast him in Tons of Money, a farce by Will Evans and Arthur Valentine, which ran for two years at the Shaftesbury Theatre. Lynn's character adopted three different personas during the play, all conniving to acquire and keep a large financial legacy. The Times commented:

Mr Ralph Lynn achieves a great triumph in his triple character, and alike as himself, as a rough diamond from Mexico, and as a naughty curate, he is extremely amusing. He is hardly ever off the stage, and to him in a great measure the success of the play should be due.

Walls played a small role in the production, as did the young Robertson Hare. The critic Sheridan Morley wrote, "the team of Walls, Hare, and Lynn was thus created, one which was to stay together for the next eleven years."