The invention relates to a clutch, in particular to a mechanical clutch suitable for space robots. According to the technical scheme, a lead screw transmission tooth meshed type clutch with the self-locking function comprises a motor, a shell, a ball screw installed in the shell, fixed teeth and movable teeth; the motor is a power input source, output of the motor is decelerated by a worm and gear to drive the ball screw to rotate, a lead screw nut moves in the axis direction of the ball screw, a fixed tooth support is pushed by a compressed spring to transversely move, the fixed tooth support drives the fixed teeth to transversely move in the shell, and the fixed teeth and the movable teeth are meshed or disconnected to achieve clutching of two parts. According to the lead screw transmission tooth meshed type clutch, the worm and gear are used for driving, on one hand, the deceleration function of the worm and gear is used, on the other hand, the self-locking function of the worm and gear is used, and the power-down brake function of the clutch is achieved; compared with the design combining a motor, a brake and a reducer, the mechanism design is simplified, and the mass is reduced; and compared with an electromagnetic clutch and the like, the beneficial effect of being large in load capacity is achieved.