Bletchley TMD is a railway traction maintenance depot situated in Bletchley, Milton Keynes in Buckinghamshire, to the north east of Bletchley railway station, on a siding off the Marston Vale line. The depot is operated by West Midlands Trains.

Bletchley is a constituent town of Milton Keynes, Buckinghamshire, England. It is situated in the south-west of the city, and is split between the civil parishes of Bletchley and Fenny Stratford and West Bletchley. In 2011, the two parishes had a combined population of 37,114.