Abstract: A case for storing a tape cassette has inner and outer cases. Peripheral walls join opposite peripheral portions of top and bottom walls of the outer case to define an opening at one side through which the inner case with a cassette therein can be inserted into the outer case. The inner case has a side member which overlies a side of the cassette and is disposed in the opening in the outer case when the inner case with a cassette therein are stored in the outer case. Top and bottom panel members extend at substantial angles from the side member to be disposed against respective top and bottom surfaces of the cassette.