The invention discloses a method for assisting electric field by adopting an insulating insulator cradle. The tool comprises the insulating insulator cradle and a seat plate, wherein the seat plate isarranged on the insulating insulator cradle, a triangular iron rod of the insulating insulator cradle is fixed on a triangular connecting plate of a strain tower connected with double strings of insulators, a metal connecting ring is connected and fixed on a main force-bearing tower material above the replaced insulator by using an insulating rope, the insulating rope is adjusted to keep the edge insulator cradle horizontal, when an electric potential electrician enters the seat plate from the tower body, the insulating insulator cradle rotates in the horizontal plane with the top of the triangular iron rod as the circle center, the electric potential electrician is brought into an electric field in a rotating mode, the equipotential electrician disassembles the seat plate and hangs theseat plate on a wire, and the insulating insulator cradle is left to complete the function of supporting the strain insulator string. The tool is advantaged in that a problem that the upper-phase andmiddle-phase electric fields of the double-loop strain tower are difficult to enter is solved, operation reliability and operation efficiency are greatly improved, and a technical guarantee is provided for ensuring safe and reliable operation of a power transmission line.