Derriaghy, (/ˌdɛrɪˈæxi/; also known as Derryaghy), (from Irish Doire Achaidh, meaning 'oak-wood of the field'), is a townland (of 538 acres) and civil parish in County Antrim, Northern Ireland, 5.5 miles (9 km) south-west of Belfast city centre. The townland is situated in the historic barony of Belfast Upper and the civil parish covers areas of both Belfast Upper and the barony of Massereene Upper.

The listed Church of Ireland building Christ Church in Derriaghy occupies the site of an early church. The earliest documentary reference to a church in Derriaghy is in a letter from Pope Innocent III in 1204. The Taxation of Down, Connor and Dromore of 1306-07 also mentions a church in Derriaghy. The records of an Inquisition in Antrim in 1605 indicate that the parish church of Dirreraghie was in some disrepair.

Derriaghy railway station was opened in 1907 and is between Dunmurry and Lambeg stations on the main Belfast-Dublin railway line. It was closed on March 1, 1953, and reopened on April 30, 1956, in response to numerous requests.

The civil parish contains the following townlands:

54°32′N 6°02′W / 54.54°N 6.03°W / 54.54; -6.03