The invention relates to interior wall paint, in particular to an environment-friendly paint which can be widely applied to the decoration of indoor walls, ceilings, plasterboards and the like, does not contain APEO (alkylphenol polyethenoxy ether), is scentless and has low free formaldehyde. The paint is prepared by mainly adopting the technology as follows: first, a dispersant, a wetting agent, a foam suppressor, a thickening agent and a mildew-proof algaecide are added into water sequentially under low speed; titanium pigment, a pH regulator, coarse whiting, calcined kaolin or washed kaolin, french chalk and a mildew-proof agent are added sequentially under medium speed; high-speed dispersion or sanding are carried out until the fineness of less than 50 Mum; and finally, a polystyrene-acrylic copolymer, a polyacrylic copolymer or a vinyl acetate copolymer-acrylic copolymer, a film-forming accessory agent, an antifreezing agent, a preservative, the foam suppressor, a rheology agent and H2O are added sequentially under low speed. The paint dose not contain APEO, thus having no effect on the reproductive system of human and animal; the paint has low odor, and no odor basically, reduces the harm of the residual monomer to human body, and has extremely good physical performances, thus being capable of meeting the requirements on indoor decoration.