Staines railway station is on the Waterloo to Reading line and is the junction station for the diverging Windsor line, in southern England to the west of London. It is 19 miles 2 chains (30.6 km) down the line from London Waterloo. It serves the town of Staines-upon-Thames in Surrey, England.

The station was opened on 22 August 1848 by the Windsor, Staines and South Western Railway, as part of its line from Richmond to Datchet. The line was further extended from Datchet to Windsor & Eton Riverside on 1 December 1849, by which time the Windsor, Staines and South Western Railway had become part of the London and South Western Railway (LSWR). The junction at Staines, together with the line to Wokingham was authorised in 1853 and built by the Staines, Wokingham and Woking Junction Railway, opening as far as Ascot on 4 June 1856 and onwards to Wokingham on 9 July 1856. From the outset, the line was leased to, and operated by, the LSWR, who purchased it outright in 1878. From Wokingham, LSWR trains continued to Reading Southern using running powers over the South Eastern Railway (SER).

In the grouping of railways in 1923, the LSWR and SER became part of the Southern Railway. In 1930 the Windsor line was electrified on the third rail system at a nominal 660 volts DC. The line towards Reading was electrified as far as Virginia Water in 1937, and throughout by 1939.

The Southern Railway was nationalised along with the rest of the railway network in 1948 and incorporated into British Railways. Following the privatisation of British Rail in the 1990s, the operation of Staines station and the trains serving it were transferred to the South West Trains train operating company, owned by the Stagecoach Group, whilst ownership and management of the track and infrastructure passed to Railtrack and, subsequently, Network Rail.

A refurbishment of the station was completed in November 2008 with ticket barriers on the platforms and a renovated ticket office. Wheelchair access to the platforms was provided by a new footbridge with lifts.

The station serves the town of Staines-upon-Thames in Surrey in southern England to the west of London and is a pre-junction/junction station for the diverging Windsor line. The Windsor Line, a branch of the longer route to Reading laid out as the original destination for the lines from London via Staines, is due to quirk of naming conventions in the rail sector, rarely referred to as a branch line. Both lines are traditionally referred to as "the Windsor Lines" and the passenger lobby group influencing the service pattern of the lines is named the Windsor Lines Passenger Group. The station is managed by South Western Railway on a contract awarded by recurring private franchise, who continue passenger services to/from London Waterloo as since the middle of the 20th century to Reading, Windsor & Eton Riverside and Weybridge.

The station was one of three – the others were Staines High Street, on the Windsor line, and Staines West, the terminus of a defunct branch of a main west-facing route from West Drayton to the north. To distinguish it from the others during their existence the station was known as Staines Central, Staines Junction and Staines Old.

All services at Staines are operated by South Western Railway.