Abstract: The building action of polyacrylate sodium(PAA-Na) on some surface active agents and detergents was stuided. For LAS, SLS etc. anionic surface active agents, it had function of improvent on detergency. It was mixed PAA-Na with appropiate builders according to optimum ratio, the detergency can equal or large than the detergency, which alone used STPP. It was a proved, PAA-Na was prospective polymer, which can replace STPP to some or total extent. In addition, it differ from STPP etc. other builder by building action, it was not chelate result.