In this work, we studied the relationship between microstructure and macroscopic deformation and the impact of alkylated graphene oxide (GO–ODA) on the change of microstructure in the stretching process at high temperature. The nanocomposites are obtained via introducing GO-ODA to poly(4-methy-1-pentene) (PMP or TPX) using a solution approach. It is found that melting points of two samples rise with the strain increasing accompanied crystal orientation during stretching process. Differential scanning calorimeter (DSC) results show that the melting points of TPX/GO-ODA (0.5 wt%) are higher than that of TPX and they all have a constant melting point at high strain. Crystallinity trends of two samples were somewhat similar with the changes of melting point. It is worth noting that the added GO-ODA makes samples reach the plateau region of the crystallinity at a greater strain than TPX. With wide-angle X-ray scattering (WAXD) analysis, crystal was destroyed in the stretching process of two samples. Small-angle X-ray scattering (SAXS) results show that the calculating fibrils diameter of TPX/GO-ODA are smaller than that of TPX. From analyzing the change process of internal structure, GO-ODA is the role of barrier and delay the molecular response to tension in the drawing process. In this work, GO, as a kind of nanofiller, is used to study the impact on crystallization behavior of polymer/filler composites during stretching process, which obviously is great significance to widen the application of GO. College of Polymer Science and Engineering, Sichuan University, Chengdu, 610065, People’s Republic of China. Address: Sichuan University, No.24 South Section 1, Yihuan Road, Chengdu , China, 610065. E-mail: yinbo@scu.edu.cn