In the 2022 Johor state election, he was reelected as the Benut assemblyman for his 4th consecutive term by defeating all of his 3 opponents, Isa Abdul Hamid from Perikatan Nasional (PN), Haniff Ghazali Hosman from Pakatan Harapan (PH) and Iskandar Noor Ibrahim from Homeland Fighters Party (PEJUANG) with a majority of 5,859 votes.
On 28 February 2020, he was sworn in as the new Menteri Besar by the Sultan Ibrahim Ismail, replacing the incumbent Dato' Dr. Sahruddin Jamal after the collapse of Pakatan Harapan (PH) state government during the 2020 Malaysian political crisis.
BN Chairman and UMNO President Ahmad Zahid Hamidi also added that he would submit the name of Hasni to the Sultan of Johor for his reappointment to the position.
However, on 14 March 2022, Hasni suddenly announced his withdrawal from the running for the position by stating that he would pave way and endorse a younger candidate to lead the state government citing long term development for Johor and the next day on 15 March 2022, caretaker EXCO member and new Machap MLA Onn Hafiz Ghazi was sworn in as the new and 19th Menteri Besar to take over him after his 2 years in office.
In the 2022 general election, Hasni wrested the Simpang Renggam seat in Johor from Maszlee Malik of PH with a majority of 1,821 votes.