Abstract: Objective To observe effects of nordihydroguaiaretic acid(NDGA) on the cell cycle of human glioma cell line SHG-44 cells. Methods The techniques of cell culture,immunohistochemisty,cell counts and FCM were employed in this study. Results ①A concentration-dependent proliferation inhibition was demonstrated in the SHG-44 cells incubated for 24 hours in the presence of NDGA,and cell proliferation was blocked in the Gl→S phase.②The most conspicuous inhibition was measured at 24 hours after treatment with 100μM NDGA for up to 96 hours.③The expression of CDK4 and cyclin Dl protein downregulated,and P16 upregulated in the cells after NDGA treatment. Conclusion NDGA can inhibit proliferation of human malignant glioma cells,and the proliferation inhibition is correlated with the decreased activity of CDK4.