To provide a tape cassette which can suppress consumption amounts of a printing tape and a bonding tape.

The tape cassette 100 has the bonding tape 74 with a thermally active adhesive applied thereon, the printing tape 17 with a printing surface to be printed, and a tape feeding roller 32 which transfers the printing tape 17 and the bonding tape 74. The tape cassette 100 can be attached to and removed from a tape printing device 110. While the tape cassette 100 being attached to the tape printing device 110, the printing surface of the printing tape 17 and the thermally active adhesive on the bonding tape 74 are brought into contact with each other on the downstream side from a printing position in an ejection direction of the printing tape. Even if the bonding tape 74 and the printing tape 17 are brought into contact with each other while the adhesive is not activated, the bonding tape 74 is prohibited from being bonded to the printing tape 17.