The invention discloses a wall-surface paint for projection and a preparation method. The wall-surface paint comprises the following components of: polyurethane resin, graphene, nano titanium dioxide, silica sol, diatomite, white carbon black, nano calcium carbonate, talcum powder, attapulgite clay, defoaming agent, cosolvent and proper amount of water. The preparation method comprises the following steps of: weighing the polyurethane resin and the graphene, adding into a reaction kettle, and reacting to prepare graphene-modified polyurethane resin; then adding the nano titanium dioxide, the silica sol, the attapulgite clay, the defoaming agent, the cosolvent and the proper amount of water, stirring uniformly, and grinding till the particle size is below 20mum; and then adding the diatomite, the white carbon black, the nano calcium carbonate and the talcum powder, and after shearing, obtaining the wall-surface paint for projection. The wall-surface paint disclosed by the invention not only can provide better picture degree and viewing comfort level for projection, but also can provide places for writing and marking of speakers, can be easy for handwriting erasing, and has better application value.