Abstract: In PUREX process, extractant and diluent are degraded by radiolysis under strong irradiation field. Some of the products of radiolysis make it difficult to strip Pu. In this paper, the ratio of radiolysis products to Pu(Ⅳ) retention was obtained by experimental study. The results show that the molar concentration ratio of HDBP to remaining Pu(Ⅳ) is about 2, and the molar concentration ratio of H₂MBP to remaining Pu(Ⅳ) is between 1 and 2. Combining with literature reports, the production of different radiolysis products in PUREX process was obtained, and the effect of different radiolysis products on Pu(Ⅳ) stripping was compared systematically. The influence of main radiolysis products on different Pu(Ⅳ) stripping processes in PUREX process was discussed. The results show that HDBP is the main radiolysis product having impact on the Pu(Ⅳ) stripping in the spent fuel reprocessing process of thermal reactor. HDBP and H₂MBP are the main radiolysis products having impact on the Pu(Ⅳ) stripping in the spent fuel reprocessing process of fast reactor.