The Lancashire Fusiliers was a British infantry regiment that was amalgamated with other Fusilier regiments in 1968 to form the Royal Regiment of Fusiliers.

The regiment was formed in 1688 in Devon under Sir Richard Peyton as Peyton's Regiment of Foot. The regiment's name changed according to the name of the colonel commanding until 1751, when it became the 20th Regiment of Foot.

The 20th Regiment of Foot was designated the East Devonshire Regiment in 1782, and the Lancashire Fusiliers in 1881.