In this paper, N-isopropyl acrylamide was synthesized by Cope elimination reaction of amine oxide from methyl acrylate and isopropylamine using diethyamine as the protective agents, hydrogen peroxide as oxidant. The oxidation reactions of DEAPAA and the yields of NIPAM were assayed by HPLC. The effect of the amount of hydrogen peroxide, catalyst and reaction temperature on oxidation reactions of DEAPAA was investigated and the influence factors,such as pyrolysis temperature, vacuum and solvent on the yield of NIPAM were analyzed. The results indicated that with sodium tungstate / sodium pyrophosphate as catalyst, double doses of hydrogen peroxide and reacting at 70℃ for 3 hours, the degree of oxidation of DEAPAA were almost 100% and the yields of NIPAM from Cope elimination reaction were 70%-72% by pyrolysis at 90℃in vacuum.