Abstract: MX (3 Chloro 4 (dichloromethyl) 5 hydroxy 2(5H) furanone) and chlorinated acetic acids such as DCA and TCA have always been the focus of Disinfection by products(DBPs) study. In order to find out the influences of reaction time, TOC, chlorine dose, pH and temperature on the formation of MX, DCA and TCA, we extracted fulvic acid(FA) from the sediment of Tai Lake, and conducted simulated chlorination of samples rich in FA, with GC/MS as analyzing instrument. Results showed positive relationship between TOC and the yields of MX, DCA and TCA. But the influences of pH, chlorine dose, reaction time, and temperature on the formation of MX, DCA and TCA are quite different and complex.