The invention relates to a high-altitude power circuit outgoing assisting device. Two rollable paying-off pulleys are arranged at the left end and the right end between a front connecting plate and a rear connecting plate, a braking screw is arranged on the upper portion of one paying-off pulley, a hanging plate is connected in the vertical direction of the left end and the right end of each connecting plate, a hook is arranged on the hanging plate at each of the left end and the right end, a static force rope is connected at each of the left end and the right end of a seat plate and can be hung in the hooks, a transverse protecting rope is connected between the left static force rope and the right static force rope, and a longitudinal protecting rope is connected between the middle portion of the front connecting plate and the front face of the seat plate. By the high-altitude power circuit outgoing assisting device, power workers protected by the longitudinal safety rope and the transverse safety rope can realize circuit outgoing by sitting on the hanging plates through the paying-off pulleys, and moving by two hands on a lead is not needed, so that a lot of physical power is saved; moving on the lead is not limited by direction, and experimental testing shows that circuit-outgoing work time is only one tenths of original circuit-outgoing work time, so that operating time, especially power failure operating time can be reduced effectively.