The invention discloses a novel lock pin device. The novel lock pin device comprises a lock pin base, a lock pin, a rotary shaft, a lock pin handle and a positioning pin. The lock pin is axially divided into a driving section, a shaft shoulder section and a lock pin section, wherein a groove is formed in the driving section. The two ends of a compression spring abut against the wall faces of a shaft shoulder and the lock pin base. A cambered-surface protrusion is arranged at the end portion of the rotary shaft, and the protrusion is arranged in the groove of the driving section of the lock pin. When the rotary shaft rotates, the protrusion can push the two side faces of the groove to drive the lock pin to move axially. The lock pin handle is fixedly connected with the rotary shaft. The positioning pin is arranged in the middle of the lock pin handle, and the two ends of a positioning spring abut against an annular protrusion and a stepped face of a stepped through hole. According to the novel lock pin device, due to the fact that the cambered-face protrusion of the rotary shaft drives the lock pin to stretch or retract axially and the lock pin is sleeved with the compression spring, the axial bumping motion of the lock pin is prevented; due to the fact that the lock pin handle is positioned by the positioning pin, the connection and disconnection of the two parts are achieved, limiting structures are both arranged at the connection position and the disconnection position, operation is flexible, no clamping phenomenon exists, and the working of the novel lock pin device is reliable.