An assembly includes a nozzle having a curved contact surface curvedly and downwardly extending from two opposite sides of a linear top ridge of the nozzle, a tire pressure sensor having a connection groove with a curved contact surface complementary in shape to and slidable relative to the curved contact surface of the nozzle, and a bolt for fastening the nozzle with the tire pressure sensor. The curved contact surface of the nozzle is slidably movable relative to the curved contact surface of the tire pressure sensor along a specific direction reciprocally so as to adjust a relative connection angle between the sensor and the nozzle and the nozzle is prohibited to move in the connection groove along other directions. Therefore, the work of using the bolt to fasten the tire pressure sensor to the nozzle can be done easily.