The present invention relates to a wall decoration coating, especially a wall ash-carbon paint paste, which is environmentally friendly and serviceable and comprises: lime, paper pulp, clay, sand, char, glutinous rice, bagasse, saline, gel powder, water and the like; grinding the clay, the sand, the char among the above materials into powders and putting the powders in the generating pool injected with water; soaking the bagasse in whitewash and putting the bagasse in the generating pool; putting and mixing the paper pulp, the saline and the gel powder in the generating pool, and soaking the same with the lime; grinding the semi-manufactures, stirring, pulping in a recycling manner, stewing is also to obtain the product through grinding, stirring, pulping, standing; and then stirring again to obtain the products. The wall ash-carbon paint paste has the advantages of using natural materials and being environmentally friendly, serviceable, anti-shedding, washable, moistureproof and free of secondary pollution.