The invention discloses a convenient-to-install transformer lightning protection device, which comprises a triangular bracket and a rotating shaft. The tail end of the rotating shaft is fixedly arranged together with the triangular bracket, and the bottom of the triangular bracket is fixedly provided with a universal wheel through a clamping groove. A rubber layer is laid on the outer surface of the rotating shaft. The outer surface of the rubber layer is fixedly provided with an air-termination system through screws. The top of the rotating shaft is further connected with a lightning arrester needle body through a coupler. A grounding net rack is laid inside the triangular bracket. The grounding net rack comprises a grounding body and a grounding main line. The grounding main line is arranged at the left end of the grounding body in an annular structure. A plurality of grounding branch lines are arranged at the tail end of the grounding main line. A connecting line interface is arranged at the top end of each grounding branch line. The entire transformer lightning protection device has the advantages of small size, small quality, convenient carrying, high reliability, low investment, high lightning protection benefit and the like. The requirement for the lightning protection of transformer equipment can be completely met.