Sir Siddiq Abubakar III, GCON, KBE (15 March 1903 – 1 November 1988) was a Nigerian Muslim leader (Sarkin Musulmi).

Abubakar was the fourth-generation heir to a two-century-old throne founded by the Shehu, the leader of the Maliki school of Islam and the Qadiri branch of Sunni.

He rapidly distinguished himself through administrative competence, skilled management of appeals from traditional courts, and his effective supervision of district and village heads, and as a result served until 1938.

His profile rose in Sokoto as his position made him accessible to the people, but it also led to tensions with Sultan Hasan dan Mu’azu Ahmadu.

He then continued to play a significant role in reducing tensions in the region after the coup and assassination of Premier Sir Ahmadu Bello, Sardauna of Sokoto, on 15 January 1966.