Abdulaziz Usman has a post-graduate degree in Business Management. Before entering politics, he was a senior planning officer for Jigawa State Agriculture And Rural Development. He was elected as a member of the House Of Representatives for 1999–2003, and was reelected for 2003-2007.
In 2005, he supported Atiku Abubakar, then the Vice President of Nigeria, in a libel claim against Newswatch magazine related to accusations of corruption while Atiku was chairman of the National Council on Privatization.
Abdulaziz Usman was elected to the National Senate for the Jigawa North East constituency in 2007. A May 2009 report by This Day said he had not sponsored any bill, although he co-sponsored some motions and sometimes contributed to debates in plenary. He was chairman of the Inter-Parliamentary Affairs Committee. In the April 2011 elections he was reelected as Senator for Jigawa North-East on the PDP platform, with 135,202 votes.