A device and method for detecting the rotation of a stud of a wind power structure comprises a rack (1), a clamping device (2), a rotating platform (3), a driving device (4), a control system (5), a traction rope (6), a gravity stretching device (7), an axis force sensor (8), a torque sensor (9), an angular displacement sensor (10), and a display (11). The clamping device (2) is fixed on the rack (1). The rotating platform (3) is provided with multiple reversing devices (3-1). One end of the traction rope (6) is connected to one unclamped end of the wind power stud, and the other end is sequentially wound across the multiple reversing devices (3-1). The gravity stretching device (7) is suspended on one end of the reversing device (3-1) finally wound by the traction rope (6). Measured data are transmitted, and a rotation-pulling force curve for representing the rotation ability can be drawn. The detection device and the detection method fill detection blanks on the rotation of the stud of the wind power structure in the nation.