Datuk Onn Hafiz bin Dato' Ghazi (Jawi: عون حفيظ بن غازي; born 2 March 1979) is a Malaysian politician who has served as the 19th Menteri Besar of Johor and Member of the Johor State Legislative Assembly (MLA) for Machap since March 2022. He previously served as MLA for Layang-Layang from May 2018 to March 2022. From March 2020 to his promotion to Menteri Besarship in March 2022, he served as Member of the Johor State Executive Council (EXCO) in the Barisan Nasional (BN) state administration under former Menteri Besar Hasni Mohammad. He is a member of the United Malays National Organisation (UMNO), a component party of the ruling BN coalition.