The invention provides a clamp for live replacement of insulators for an overhead line, relating to a clamp for live replacement of insulators. The clamp provided by the invention solves the problems of the existing clamp for live replacement of the insulators for the overhead line that a first insulator at a cross arm side can not be replaced, different complicated tools need to be used for replacing a single insulator and a whole string of insulators, and the labor intensity of operators is high. The clamp comprises a clamp main body, a U-shaped slot baffle plate, a lead screw baffle plate, a first bolt, two lead screw components and a plurality of second bolts, wherein the two lead screw components are symmetrically positioned at the left end and right end of the clamp main body; a chock block is fixedly connected with a lead screw slot through the lead screw baffle plate; the lead screw baffle plate is fixedly connected with the clamp main body through two second bolts; the U-shaped slot baffle plate is fixedly connected with the clamp main body through the first bolt; and a clamping plate on the U-shaped slot baffle plate is positioned at the upper end of the clamp main body. The clamp for live replacement of the insulators for the overhead line, provided by the invention, is used for live replacement of the insulators.