The palmitamidopropyl betaine (PAPB) type amphoteric surfactant was synthesized by sodium choloroacetate and palmitamidopropyldimethyl tertiary amine that was synthesized by an amidation with palmitic acid and N,N-dimethyl-1,3-propanediamine as raw material. The effects of reaction temperature and time, the molar ratio of palmitic acid to N,N-dimethyl-1,3-propanediamine, the amount of catalyst, 4 A molecular sieves on conversion of palmitic acid were studied. Meanwhile, the structure of product was characterization by FTIR and 1HNMR, and properties of palmitamidopropyl betaine and the mixed surfactant systems were investigated. The results showed that the optimum conditions of amidation reaction were screened out as follows: reaction temperature of 160℃ and reaction time of 10 h, the molar ratio of N,N-dimethyl-1,3-propanediamine to palmitic acid 1.05:1, the amount of catalyst KOH of 0.5%. Under the above conditions, the conversion of palmitic acid was 92.41%. The critical micelle concentration and surface tension of palmitamidopropyl betaine were 1.12×10-4 mol•L-1 and 31.63 mN•m-1, respectively, and its solubilization capacity of benzene was 4980mL/mol.