The 39th Infantry Brigade was a military formation of the British Army that was first established during the First World War and reformed in the 1950s.

The brigade was detached from the division on 1 July 1918 and posted to North Persia Force where it remained until 31 August 1919.

Its first operational summons was in October that year, when it was moved to Cyprus aboard two aircraft carriers, and then on to Egypt.

In February 1953, it was warned for movement to carry out anti-Mau Mau operations with East Africa Command in Kenya.

From August 1969, the Brigade, as 39 Airportable Brigade, was involved in The Troubles in Northern Ireland, eventually taking on responsibility, under HQ Northern Ireland, for an area including Belfast and the eastern side of the province, but excluding the South Armagh border region.