The invention relates to an outer insulating antifouling cleaning device for power transmission and transformation equipment. The device comprises cleaning pieces (2), tracks (3), brushing heads (4), fixed rings (5), a horizontal rod (6), a motor driving device (7), a foul detecting device (8), belt wheels (10) and a transmission shaft (11), the belt wheels (10) are fixed on the transmission shaft (11) and meshed with the tracks (3), the horizontal rod (6) is fixedly mounted at the uppermost end of a central insulator shaft, and the foul detecting device comprises an ultraviolet sensor, a single chip microcomputer and a second storage battery. The outer insulating antifouling cleaning device for the power transmission and transformation equipment can effectively clear foul on the surface of an insulator to lower probability of flashover.