4A zeolite is being increasingly used in detergent in place of sodium tripolyphosphate (STPP) .Inthiss paper ,4A; zeolite was synthesized directly from kaolin without adding aluminium compound.The results show that the exchange capacity of calcium is 280~310mg.CaCO3/g(dry) ,the average diameter of a particle is 4.10 um, the relative whiteness is 85~91% ,and pH≤11 The raw materials were collected from Jiahe of Xuzhou in Jiangsu Province and Datong kaolin mine in Shanxi Province. The optimum SiO2/Al2O3 molar ratios of these two sorts of kaolins are about 2, being highly pure (kaolinite﹥95%) and easy to pretreat by means of calcination. The activity of kaolin in the process of calcination, the formation and aging of gel and the crystallization of 4A; zeolite were studied through experimentation.The optimal processing conditions were selected for different kaolins in accordance with their different structures and compositions.The recycle of mother liquors was resolved in order to reduce costs of the process.The author investigated the effect of reaction time ,alkalinity ,solid contents in synthesized mixtures and mechanical forces on the synthesis of 4A; zeolite.