Aminuddin bin Harun (Jawi: أمين الدين بن هارون; born 2 January 1967) is a Malaysian politician who has served as the 11th Menteri Besar of Negeri Sembilan since May 2018, Member of the Negeri Sembilan State Legislative Assembly (MLA) for Sikamat since March 2008 and Member of Parliament (MP) for Port Dickson since November 2022.

He received his secondary education at Sekolah Menengah Kebangsaan Tanah Merah, Port Dickson before furthering his studies at the MARA Institute of Technology (now UiTM) in the field of business.

From 1991, Aminuddin served a five-year tenure as an investigative officer in the Anti-Corruption Agency (ACA, now MACC).

Prior to joining PKR in 1999, he was a member of United Malays National Organisation (UMNO), a component party of the Barisan Nasional (BN) coalition and has been its secretary for Kampung Pachitan division from 1995 to 1998.

[3] Aminuddin submitted a letter of endorsement by PKR President Wan Azizah Wan Ismail to DYMM Yang di-Pertuan Besar of Negeri Sembilan as the next Menteri Besar of Negeri Sembilan after PH gained the majority of State Legislative Assembly in the 2018 general election to form the new state government.