TCDD DE21500 were diesel-electric locomotives built for operations on Turkish State Railways. Forty General ElectricU20C units with GE engines were built in 1964–65. Most of the locomotives are retired from service. The locomotive was a part of the State Railways' dieselisation of its network and was the first mainline diesel locomotive. Most of them were retired in the early 2000s, with a few seeing service into the later half of the decade.
