The development comes after opposition parties brought forward a case that Prayuth, who seized power in a military coup in 2014, has overstayed his term in office, the BBC reported.
Thailand’s constitution limits prime ministers to eight years in office.
Prayuth had retained office in 2019 under a military government guided election.
Deputy Prime Minister Prawit Wongsuwan, also a former army chief, will likely become the interim Prime Minister, according to the cabinet line of succession.