The invention relates to a device for testing the mechanical characteristic of a tunnel locking anchor pipe and a testing method for the device. The device is applied to design and construction; the design can be guided; the construction difficulty is lowered; and a guarantee of the construction safety and the tunnel structure stability is facilitated. According to the technical scheme provided by the invention, the device comprises a locking anchor pipe body; a conical head is arranged at one end of the locking anchor pipe body; four round holes are evenly formed in the circumference; a strain gage is adhered to one side of each round hole and is connected with a connection terminal; each connection terminal is connected with a lead; and the other end of each lead is connected with a strain tester. The testing method comprises the steps as follows: aiming at testing of axial stress of various sections of the locking anchor pipe, the axial strain is measured by virtue of the strain tester by a resistance strain gage half-bridge single-arm temperature compensation connection method; and aiming at testing of bending moments of the sections of the locking anchor pipe, the compressive or tensile strain caused by the bending moments is measured by the strain tester by a resistance strain gage half-bridge double-arm connection method.