A tape cartridge 11 includes a platen roller 15, when the tape cartridge 11 is mounted on a tape printer 1, a print head 22 of the tape printer 1 contacting the platen roller 15 with a print tape T and an ink ribbon R arranged therebetween such that the print head 22 can be separated from the platen roller 15; a cartridge case 16 that houses the print tape T, the ink ribbon R, and the platen roller 15; and an insertion opening 17 formed in the cartridge case 16, the print head 22 being inserted into the insertion opening 17. A contact portion 10 of the platen roller 15 that is brought into contact with the print head 22 protrudes relative to a head receiver 72 of the insertion opening 17 to which the print head 22 is exposed.