Provided is a machine tool hand including a body portion that is mounted so as to be attachable to and detachable from a spindle of a machine tool, and that is provided with a flow path connected to a coolant-liquid supply path formed in the spindle; and two or more hand members that are attached to the body portion such that at least one of the hand members is pivotable about a prescribed axis, and that are capable of gripping an object therebetween by being closed. The flow path is provided with discharge ports via which a coolant liquid supplied from the coolant-liquid supply path is discharged toward surfaces of the hand members that are exposed to an outside, and a pressure of the coolant liquid causes an opening operation or a closing operation of the hand members.