The crystallization behavior of polychloroprene rubber (CR) has been studied in this work. Differential scanning calorimetry (DSC) was applied to characterize the crystallization behavior. And X-ray diffraction was applied to determine the impact of crosslinking on the crystallization of CR. Synchrotron X-ray diffraction (SXRD) method was applied to study the dynamic crystalline behavior. On the basis of the experimental results, it is found that crosslinking will hamper the crystallization of CR while large strain can restore this course. And this is in accord with the Mooney-Rivlin analysis result. Detailed discussion was offered circling around this phenomenon. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 121: 37-42, 2011