A pavement structure interlayer bonding torsion testing device comprises a metal base plate, a sensor unit and a threaded sleeve. The metal base plate is used for bonding with the surface of a pavement core sample, and a first bolt is arranged at the surface center of one side, away from the pavement core sample, of the metal base plate. The sensor unit comprises a torsion sensor, a lower flange seat and an upper flange seat, the lower flange seat and the upper flange seat are fittingly locked to shaft ends of the torsion sensor, and a second bolt is arranged at the surface center of one side,away from the torsion sensor, of the lower flange seat. The surface center of one side, away from the torsion sensor, of the upper flange seat is provided with a test load input end. The threaded sleeve is used for connection with the first bolt and the second bolt. The pavement structure interlayer bonding torsion testing device and method have advantages that onsite quantitative measurement ofpavement structure interlayer bonding torsion can be realized, and simplicity in operation and accuracy in measurement are achieved.