Abstract: This paper indicates that making useful of waste water from silk reeling synthetically in agricultural engineering is available and practicable through the studying of three kinds of models as follows, i. e. planting lotus root -rasing fish, Mlternanthera philoreroides-planting wild rice stony-arrowhead, Alternantheraphiloxeroides-planting wild rice stem -arrowhead-lotus root. Also we analyse the effects of the varities of aquatic plant, air temperature and the field plot keeping apart to the purification of water.