Amphoteric comb like copolymers with different molar ratios of anionic to cationic groups in main chain were synthesized and characterized. The effects of molar ratio of anionic to cationic groups in comb like copolymers on dispersion, dispersability retention, adsorption behavior and early hydration behavior in fresh cement suspensions were investigated systematically to elucidate the mechanism of copolymers. These results indicate that moderate incorporation of cationic groups into comb like copolymers improved the dispersability of cement pastes. However, when the content of cationic groups was further increased, as the adsorbed amount of amphoteric copolymers was increased, the dispersibility of cement pastes became worse. The dispersability retention of cement pastes was enhanced with the increase of cationic groups content in main chain of amphoteric copolymers. Besides, there is a negative correlation between the dispersability retention ratio and copolymer concentration in solution. The adsorption sites, adsorption conformation and early hydration behavior together should be considered to explain its dispersion and the dispersability retention of cement pastes with amphoteric copolymers. In addition, there exists an optimal balance in the molar ratios of anionic to cationic groups in backbone of comb like copolymers.