State elections were held in South Australia on 25 November 1989. All 47 seats in the South Australian House of Assembly were up for election. The incumbent Australian Labor Party led by Premier of South Australia John Bannon defeated the Liberal Party of Australia led by Leader of the Opposition John Olsen. Labor won 22 out of 47 seats, and secured a majority of 24 with the support of two Independent Labor members.

The House of Assembly, or lower house; Is one of the two chambers of the Parliament of South Australia. The other is the Legislative Council. It sits in Parliament House in the state capital, Adelaide.