A tablet cassette is provided that can easily adjust the depth etc. of a guide groove of a rotor depending on the size of a tablet to be dispensed. The tablet cassette includes movable pieces that are disposed movably in a radial direction of the rotor in the plurality of tablet guide grooves and form surfaces in the radial direction of the rotor in the tablet guide grooves, and a movable piece moving mechanism that moves the movable pieces in the radial direction of the rotor.
