Abstract: In this work, crosslinked polyethylene samples were prepared by compression molding and rotational molding methods, and then effects of molding methods on dropweight impact strength at different temperature, crystal size, crystallinity degree and gel content at different thickness gradients of crosslinked polyethylene were investigated. The results indicated that the dropweight impact strength of the compressionmolded sample increases from 29 J/mm to 35 J/mm when test temperature was reduced from 25 ℃ to -40 ℃, but the sample kept an identical microstructure in different gradient thicknesses. For the rotational molded sample, the dropweight impact strength at -20~25 ℃ and -40~-30 ℃ is about 29 and 1 J/mm, respectively. There is a ductilebrittle transition between -20 and -30 ℃, and the microstructures also kept an identical microstructure in different gradient thicknesses except for the innermost surface layer around 0.2 mm. The inner surface layer has a lower gel content, higher crystal size and higher crystallization degree in comparison with other gradient thicknesses. Moreover, the microstructures of the innermost surface layer dominated the dropweight impact performance at low temperature.