A tire pressure gauge, includes: an enclosure with an intake hole, a gas nozzle assembly connected with the enclosure, and an internal thread nut member, the gas nozzle assembly comprising a stem, a first threaded bolt, a second threaded bolt, and a nut screwed onto the first threaded bolt, the internal thread nut member comprising an insertion portion and a limiting portion, a stepped hole being defined in the enclosure, extending through a top portion and bottom portion of the enclosure, and engaging the internal thread nut member, the insertion portion of the internal thread nut member being inserted into the stepped hole and connected with the second threaded bolt of the gas nozzle assembly, and the limiting portion of the internal thread nut member being pressed against the enclosure.
