The invention provides a street tree coating material and a preparation method therefor. The street tree coating material mainly comprises a pyrethroid ingredient, a reflecting ingredient, a heat insulating ingredient, an aqueous synthesized resin emulsion ingredient, a coating film structure improving ingredient and a photo-stabilization ingredient. The street tree coating material prepared from pyrethroid, glass micro-beads, an aqueous synthesized resin emulsion, diatomite or kaolin and nano zinc oxide not only has a good long lasting disinsectization effect, but also can be used for effectively preserving heat, the invasion to trees caused by cold is reduced, meanwhile, light can be effectively reflected, and street trees can play a good role in guiding traffic, so that the traffic safety of roads is greatly improved.