The station was the first of three planned by London Passenger Transport Board (LPTB) in 1935 to extend the Northern line from Edgware to Bushey Heath.
There was debate about the name for the station, with Edgwarebury, Edgebury, Canons, North Edgware and All Souls all being proposed.

The extension was part of the Northern Heights project to electrify steam-operated London and North Eastern Railway (LNER) branch lines and incorporate them into the Northern line.
Much of the land for the extension came from the purchase in 1922 by the LPTB's precursor the Underground Electric Railways Company of London of the unbuilt Watford and Edgware Railway (W&ER).
The W&ER had planned an extension of the Edgware, Highgate and London Railway to Watford Junction via Bushey, but it had never raised the capital required and its powers to construct a line had expired in 1911.
The specific route to Bushey Heath was approved by parliament in October 1937.
The LPTB's principal purpose for the extension to Elstree was to stimulate the development of new residential areas to increase passenger numbers.
A secondary purpose was to provide a location suitable for a large new depot that was required to accommodate and maintain the new fleet of 1938 Stock trains to be used across the existing Northern line and the lines taken over from the LNER.

Brockley Hill station was to be located on a viaduct to the north of the existing junction of Edgware Way and Spur Road.
The T-junction was to be reconstructed as a roundabout to incorporate a forecourt for access to a curving range of shops and a continuation of Spur Road heading to the north-east to a new housing development.
The station was designed by the LPTB's architectural department in conjunction with the estates department of All Souls College.
The station platforms were to be on the viaduct and on a bridge over Spur Road and were to be long enough for nine-car trains being planned for the new Northern line service.
The ticket hall was to be located under the bridge with stairs up to the platforms and provision for escalators to be installed later.
The station was to be provided with a car park for 20–25 cars.

Construction on the Northern Heights project began in the late 1930s but was interrupted by the Second World War.
Most of the work to that date had been carried out on LNER branch tracks, but work between Edgware and Bushey Heath had started in June 1939.
The route of the line had been cleared and laid out and some earthworks and tunnelling carried out between Edgware and Elstree South.
At the site of Brockley Hill station and south of Edgware Way, construction of the piers of the viaduct had begun and three out of 12 arches at Brockley Hill station had been completed by August 1939.
Following the outbreak of war in Europe, work on the station and the extension was suspended in September 1939 and was formally terminated in December of the same year as wartime funding restrictions would prevent completion.
During the war years, the LPTB-owned land was used for farming vegetables for staff canteens.
The station was the first of three planned by London Passenger Transport Board (LPTB) in 1935 to extend the Northern line from Edgware to Bushey Heath. There was debate about the name for the station, with Edgwarebury, Edgebury, Canons, North Edgware and All Souls all being proposed.
The extension was part of the Northern Heights project to electrify steam-operated London and North Eastern Railway (LNER) branch lines and incorporate them into the Northern line. Much of the land for the extension came from the purchase in 1922 by the LPTB's precursor the Underground Electric Railways Company of London of the unbuilt Watford and Edgware Railway (W&ER). The W&ER had planned an extension of the Edgware, Highgate and London Railway to Watford Junction via Bushey, but it had never raised the capital required and its powers to construct a line had expired in 1911. The specific route to Bushey Heath was approved by parliament in October 1937. The LPTB's principal purpose for the extension to Elstree was to stimulate the development of new residential areas to increase passenger numbers. A secondary purpose was to provide a location suitable for a large new depot that was required to accommodate and maintain the new fleet of 1938 Stock trains to be used across the existing Northern line and the lines taken over from the LNER.
Brockley Hill station was to be located on a viaduct to the north of the existing junction of Edgware Way and Spur Road. The T-junction was to be reconstructed as a roundabout to incorporate a forecourt for access to a curving range of shops and a continuation of Spur Road heading to the north-east to a new housing development. The station was designed by the LPTB's architectural department in conjunction with the estates department of All Souls College. The station platforms were to be on the viaduct and on a bridge over Spur Road and were to be long enough for nine-car trains being planned for the new Northern line service. The ticket hall was to be located under the bridge with stairs up to the platforms and provision for escalators to be installed later. The station was to be provided with a car park for 20–25 cars.
Construction on the Northern Heights project began in the late 1930s but was interrupted by the Second World War. Most of the work to that date had been carried out on LNER branch tracks, but work between Edgware and Bushey Heath had started in June 1939. The route of the line had been cleared and laid out and some earthworks and tunnelling carried out between Edgware and Elstree South. At the site of Brockley Hill station and south of Edgware Way, construction of the piers of the viaduct had begun and three out of 12 arches at Brockley Hill station had been completed by August 1939. Following the outbreak of war in Europe, work on the station and the extension was suspended in September 1939 and was formally terminated in December of the same year as wartime funding restrictions would prevent completion. During the war years, the LPTB-owned land was used for farming vegetables for staff canteens.
Brockley Hill tube station