A tape cartridge to be mounted in a tape printing apparatus including plural push switches which project from a mounting circumferential wall includes plural detection target portions that is provided on an outer circumferential surface of the tape cartridge and to be opposed to the plural respective push switches when the cartridge is mounted in or unmounted from a cartridge mounting unit of the tape printing apparatus. Each of the plural detection target portions has a slide portion that extends in the mounting/unmounting direction and operates the associated push switch while sliding when the cartridge is mounted in the cartridge mounting unit.