A chair type massage machine 100 includes a seat part 200, a backrest part 300 which is rotatably supported at the back of the seat part 200 and is capable of reclining, a base part 400 provided at the left and right sides of the seat part 200, arm treatment parts 500 provided above the base part 400, and which move front and back with respect to the base part 400 to treat a forearm of a person to be treated, and an operation unit 700 which receives operation inputs by the person to be treated. The backrest part 300 includes a frame 310, and the frame 310 is made from a first frame 311 and a second frame 312.