The film's title - The Mouse That Roared - has entered common usage as a description of an unexpected triumph scored by something or someone small and/or unheralded. It has been used to refer to everything from the American craft beer industry to, most recently, the country of Kyrgyzstan, site of a strategic American airbase used in the war in Afghanistan.

Leonard Wibberley published four sequels to The Mouse That Roared: Beware of the Mouse (1958), The Mouse on the Moon (1962), The Mouse on Wall Street (1969) and The Mouse That Saved the West (1969).

In 1963, Walter Shenson produced a sequel, The Mouse on the Moon, based on Wibberley's third Grand Fenwick novel. Peter Sellers was unavailable, so Margaret Rutherford and Ron Moody played the Grand Duchess and the Prime Minister, respectively. David Kossoff returned to play Professor Kokintz, who this time discovers a new rocket fuel that puts Grand Fenwick into the space race.

While working as an executive for CBS, Jack Arnold shot the pilot for a TV series based on The Mouse That Roared, with Sid Caesar cast in Sellers' three roles. The pilot did not sell.

The 1970 stage version of The Mouse That Roared by Christopher Sergel is a popular item with community and high-school theatres.

Henry A. Giroux titled his 2001 study of the influence of the Disney Company's growing power in the media The Mouse That Roared.

The rock group The Mouse That Roared released the 2006 CD Excommunicator, with music written by Stephen Kozik (aka Cloister Maximus III), former drummer for Minmae. They followed a year later with Pop Tomorrow.

John Fumasoli and the Jones Factor titled a 2007 jazz number "The Mouse That Roared."

by Frank Miller