The 21st (East Africa) Infantry Brigade was a brigade sized formation of the British Army, which was founded on 31 August 1939 in British East Africa.

The brigade was composed of units from the King's African Rifles and the Northern Rhodesia Regiment.

[1] During the Second World War, the brigade formed part of the 1st, 11th, and the 2nd (African) Division.

The brigade took part in the East African, and the Burma Campaigns.

It ended the war based inside British India.