Datuk Mohamaddin bin Ketapi (born 3 June 1957) is a Malaysian politician who has served as Member of the Sabah State Legislative Assembly (MLA) for Segama since September 2020.

He is a member of the United Malays National Organisation (UMNO), a component party of the Barisan Nasional (BN) coalition.

[4] However on 28 June 2022, he left BERSATU and became independent again in support for BN and GRS ruling coalitions after joining it only seven months prior.

Mohamaddin supports the curfew that was imposed in eastern Sabah to combat the rampant cross border crimes perpetrated by bandits from the neighbouring southern Philippines.

[8] In the 2018 election, Sabah Heritage Party (WARISAN) fielded him to contest the Silam parliamentary seat,[9] facing the incumbent candidate Nasrun Mansur from the United Malays National Organisation (UMNO) and subsequently won.