The invention discloses a lightning arrester preventing birds and having an excrement collecting function, the lightning arrester includes a mounting plate, the top of the mounting plate is fixedly connected with the lightning arrester, the top of the mounting plate is fixedly connected with cleaning boxes on both sides of the lightning arrester, one side of the inner wall of the cleaning box is slidably connected with an electric telescopic rod, the other end of the electric telescopic rod is fixedly connected with an arc block, one side of the arc block penetrates through the cleaning box and extends to the outside of the cleaning box, and relates to the technical field of lightning arrester equipment. The lightning arrester has the function of collecting excrement, By cleaning the brushmovement, the bird droppings on the surface of the lightning arrester can be cleaned well, And through the movement of the friction cleaning block, the residue and trace of the lightning arrester after cleaning can be cleaned, which greatly improves the effect of lightning arrester cleaning, avoids the bird droppings affecting the normal operation of the lightning arrester, and prolongs the service life of the lightning arrester.