He is a member of the board of governors of the Bangladesh Enterprise Institute.
[3] Mannan was elected to Parliament from Manikganj-2 as a candidate of Jatiya Party in 2008.
[6] He was a member of the Parliamentary Standing Committee on Industries Ministry.
[7] While campaigning for the general elections in 2018 from Manikganj-2 constituency Mannan's motorcade was attacked allegedly by Awami League activists.
[8][9] Momtaz Begum, the Awami League candidate won the election.