St Joseph's Rapogi High School in Migori County has been closed following two dormitory fires.
Students were sent home on Tuesday evening after a board of management meeting.
"The closure is important in allowing investigating agencies to do their work," board member Ondu Abade said, adding that the students will resume their studies next week.
The incidents occurred on Monday night.
The school now joins a long list of institutions in Nyanza and Western regions that have been occasioned by dorm fires.
County police boss Joseph Nthenge said investigations are underway.
"We have launched high level investigations to establish the cause of the fire. We ask members of staff and students who might have any clue to volunteer information to the police," Mr Nthenge said.