Variable shape mirror, laser processing apparatus, and method for manufacturing variable shape mirror

A variable shape mirror (10) is provided with: a reflecting mirror (11) having a reflecting surface that reflects light; a first support member (21) having a first plate portion and a first fixing member and supporting the mirror; a second support member (31) having a second plate portion and a second fixing member and supporting the mirror; and an adjustment member that changes the distance between the first plate portion and the second plate portion. The first plate portion is disposed at a predetermined interval from the rear surface of the mirror. The first fixing member is connected to the first plate portion, and when m is an integer greater than or equal to 2, the mirror is fixed by m first fixing portions of the mirror. The second plate portion is disposed at a predetermined distance from the back surface of the mirror across the first plate portion. The second fixing member is connected to the second plate portion, and when n is an integer greater than or equal to 2, the mirror is fixed by n second f