Mary Okanson Owusu is a Ghanaian jurist. Currently a judge of the Appeal Court, she was nominated Supreme Court Judge in November 2019 and vetted on 9 December 2019. She was sworn in on 17 December 2019.

Prior to her appointment, she had served on the bench for thirty-eight (38) years.

Mary Okanson Owuoa hails from Beposo in the Ashanti Region of Ghana. She had her secondary education at T.I. Ahmadiyya Secondary School, Kumasi (T.I. Amass) from form one to upper six.

She began serving on the bench as a District Magistrate from 1990 to 1992. She became a Circuit Court judge in 1992 and served in that capacity until 2000 when she was made a High Court judge. In 2003, she was appointed as the supervising High Court judge for Sunyani until 2005.

She remained a High Court judge until 2006 when she sat on the Court of Appeal. She had been a justice of the Court of Appeal until her nomination for the role of Supreme Court Judge in November 2019. She was sworn into office on 17 December 2019.

Justice Owuoa has served as the president of the Ghana Chapter of the International Association of Women Judges for a period of four years. She has also served as a member of the Ethics Committee of the Judicial Service. From 2010 to 2014, she was a member of the Performing Assets Committee, Judicial Service.