Mrs Tinubu was elected on Saturday at the 29th Ordinary General Assembly of the organisation in Addis Ababa, Ethiopia.
The first lady of Sierra Leone, Mrs Fatima Bio, was elected as the President of OAFLAD, while the first lady of Angola, Mrs Ana Lorenzo, was elected Vice President.
Mrs Tinubu joins the eight-member steering committee as one of the two members representing West Africa.
Other member nations elected to the committee include Sierra Leone, whose first lady is the new President of the organisation; Angola, whose first lady is the Vice President; Malawi, Kenya, Ethiopia, Equatorial Guinea and Congo.
The election was conducted on the sidelines of the 38th Ordinary Session of the Assembly of the Heads of State and Government of the African Union, held from February 13 to 16.
OAFLAD members comprise the spouses of African heads of state and government from 24 countries across the continent.
Mrs Tinubu congratulated Bio and promised to keep pushing forward to ensure that women and girls in Africa have access to standard education.
The Secretary-General and the outgoing President of OAFLAD, Ms Nardos Berhanu, and the first lady of Namibia, Mrs Monica Geingos, also congratulated Mrs Tinubu and other elected members.
