One object of this application is to provide an advanced substrate holder including a clamper. A substrate holder holds a substrate by interposing the substrate between frames. The substrate holder includes a front frame, a rear frame, and one or a plurality of clampers. Each of the clampers includes a hook portion including a hook base and a hook main body, and a plate including at least one claw. At least one of the clampers includes the plate including a first claw for a lock and a second claw for a semi-lock.