Los Angeles County Sheriff's Department said Ricardo Medina, 36, who played the Red Ranger on Power Rangers Wild Force in 2002 and later played Deker on Power Rangers Samurai, was in custody over the death of Joshua Sutter.
Police said Medina and Mr Sutter got into an argument on Saturday afternoon that turned into a fight.
Medina retreated to his bedroom with his girlfriend, but when Mr Sutter forced his way into the room, Medina grabbed a sword he kept near the door and stabbed his room-mate in the stomach, according to authorities. He then called emergency services and waited for help.
Medina called 911, waited at the scene and was booked for murder at Palmdale Sheriff Station, where he is being held in lieu of $1 million bail, the department said.
Medina is expected to appear in Antelope Valley Courthouse on Tuesday, according to documents on the department's website.