[Problem] To provide a tablet guide path-adjusting device of a tablet cassette, wherein the dimensions of a tablet guide path can be automatically and quickly adjusted according to the shape or size of a tablet. [Solution] This tablet guide path-adjusting device adjusts tablet guide path-adjusting mechanisms of a tablet cassette provided with: a rotor 8 rotatably disposed in a cassette body 5 and having a tablet guide path 8a that accommodates at least one tablet stored in the cassette body and guides the tablets to a discharge hole 9 of the cassette body； a partition member 20 which enters the tablet guide path and is positioned between the lowermost tablet and a tablet above the lowermost tablet； and the tablet guide path-adjusting mechanisms M2, M3, M4 configured to adjust, in the rotor, at least one dimension among the depth and the width of the tablet guide path 8a, wherein the tablet guide path-adjusting device engages with engagement parts 33c, 52b, 95d of the tablet guide path-adjusting mechanisms to operate the tablet guide path-adjusting mechanisms, and adjusts the dimensions of the tablet guide path according to the shape or size of the tablets.
