ABSTRACT: Through the influence process analysis of clay on the performance of Polycarboxylate (PCE), a high density cationic polymer has been designed and synthesized. The molecular structure of Concrete Anti-Clay Additives (CACA) was measured by Fourier transform infrared spectrometer. The effect of CACA upon the dispersion of PCE was investigated by mini slump test. The adsorption of PCE and CACA on clays or cement was determined by the method of total organic carbon. The results showed that CACA have obvious resistance to clay due to the strong ability of selective absorption.