Frimley is a town in the Borough of Surrey Heath in Surrey, England, approximately 30 mi (48 km) southwest of central London. The town is of Saxon origin, although it is not listed in Domesday Book of 1086.

Train services to Frimley (on the line between Ascot and Aldershot), are operated by South Western Railway.

The name Frimley is derived from the Saxon name Fremma's Lea, which means "Fremma's clearing". The land was owned by Chertsey Abbey from 673 to 1537 and was a farming village. More recently it was a coach stop on a Portsmouth and popular Southampton road for about four hundred years.

Frimley was not listed in Domesday Book of 1086, but is shown on the map as Fremely, its spelling in 933 AD.

Frimley Lunatic Asylum was opened in 1799; it catered for both male and female patients, and received four patients from Great Fosters, Egham. Magistrates visited in 1807 and ordered the proprietors to stop chaining the patients.

An 1811 inventory from Frimley, a Workhouse, can be seen on the Surrey County Council website.

The present St. Peter's Church was built in 1826 replacing earlier buildings. The building has a balcony running around three sides of the interior. Dame Ethel Smyth once preached from the pulpit.

In 1904, the Brompton Hospital Sanatorium was established in Frimley to treat tuberculosis patients; it closed in 1985. Dr Marcus Sinclair Paterson (1870-1932) was the first medical superintendent, and he developed a system of treatment called 'graduated labour' which generated a lot of interest from other health professionals. The treatment used controlled levels of physical activity.

In 1931 the staff at Frimley Cottage Hospital were unable to save the life of Lieutenant Hubert Chevis, who had been admitted, along with his wife Frances, after eating poisoned partridge meat. He died of strychnine poisoning. The case remains an unsolved murder mystery.

In 1959 the Cadet Training Centre at Frimley Park was formed following the 1957 publication of the Amery Report.

2 December 1958, a Hunting-Clan Vickers Viscount 732 (registration: G-ANRR) on a test flight following a major overhaul. While flying at 1,000 ft (300 m) 10 minutes after takeoff from London Airport, the aircraft lost its starboard wing. This caused the aircraft to crash near the village and catch fire, killing all six occupants. Accident investigators established the reverse operation of the elevator spring tab as the probable cause. Incorrect maintenance of the spring tab mechanism and failure to notice the tab's faulty operation as a result of negligence on the part of maintenance personnel, who were responsible for inspecting the aircraft before returning it to service, involved the pilot in command in involuntary manoeuvres that overstressed the aircraft. This in turn resulted in the aircraft's right wing breaking off.