A polycrystalline diamond compact drill bit includes a steel body connector and a matrix crown. The matrix crown is provided with multiple main blades extending axially. A rear end surface of the matrix crown is provided with a connecting block projecting backwardly. A front end surface of the steel body connector is provided with a connecting groove having a shape matching a shape of the connecting block. The connecting block is inserted into the connecting groove to form an interference fit with the connecting groove. The rear end surface and the front end surface are fitted to each other. The periphery of the connecting block is provided with an inner positioning hole. A periphery of the steel body connector is provided with an outer positioning hole penetrating into the connecting groove at a position corresponding to the inner positioning hole.