Deli Serdang is a regency in the Indonesian province of North Sumatra. It surrounds the city of Medan, and also borders to the west the city of Binjai, which is effectively a bedroom community for Medan. The entire regency lies within the Medan metropolitan area. It occupies an area of 2,241.68 km2. The capital of the district is Lubuk Pakam, which is located approximately 30 km east of Medan. The national census of 2000 recorded 1,573,987 people, but by 2010 the regency's population increased by 13.76% to 1,790,431, and at the 2020 Census the total was 1,931,441. The official estimate as at mid 2023 was 2,018,164. Kualanamu International Airport is located in this regency.

The Greater Medan metropolitan area, known locally as Mebidangro is a metropolitan area in North Sumatra, Indonesia, which consists of Medan City, Binjai City, Deli Serdang Regency and part of Karo Regency. The metropolitan area was established by a presidential decree in 2011. It is a leading economic centre in western Indonesia, especially for provinces of Aceh, North Sumatra, West Sumatra and Riau. The metropolitan area also serves as a hub for western Indonesia.