The Colony of Aden or Aden Colony (Arabic: مستعمرة عدن Musta‘marat ‘Adan) was a British Crown colony from 1937 to 1963. It was located in the south of contemporary Yemen. It consisted of the port of Aden and its surroundings (an area of 192 km2 (74 sq mi)).
Before 1937, Aden had been governed as part of British India. Under the Government of India Act 1935 the territory was detached from British India, and was made a separate colony of the United Kingdom; this separation took effect on 1 April 1937.
On 18 January 1963, the colony was reconstituted as the State of Aden (Arabic: ولاية عدن Wilāyat ʿAdan) within the new Federation of South Arabia. The federation in turn became the People's Republic of South Yemen on 30 November 1967, marking the end of British rule.
The hinterland of the Colony of Aden was separately governed as the Aden Protectorate.