Abstract: Objective To investigate the effect of aquaporin-4(AQP4) on the severity and migration of astrocytoma. Methods Clinical tissue specimens were collected. Normal astrocyte, low-grade astrocytoma cells and high-grade astrocytoma cells were cultured from these specimens. Aquaporin-4 gene relative amount was detected by realtime fluorescence quantitative PCR. And the expression of aquaporin-4 protein was detected by Western blot. The migration of cells was measured with Transwell assay. Results The amplification of AQP4 gene in low grade group and high grade group were (1.65±0.052) and (2.04±0.196) separately, with statistically significant difference(P<0.05). Western blot results suggested that AQP4/β-actin grey value were (0.103±0.012) in control group, (0.185±0.100) in low grade group, (0.248±0.028) in high grade group, with significant difference (P<0.05); the level of aquaporin-4 protein was increased along with the growing of cell malignant degree(P<0.05). Transwell assay results suggested that the absorbance of cell destaining solution were (0.408±0.010) in control group, (0.590±0.033) in low grade group, (0.986±0.026) in high grade group, with significant difference (P<0.05). The cell migration ability was increased along the increasing of AQP4 expression(P<0.05). Conclusion Aquaporin-4 is contained in astrocytoma. With the increasing of malignant degree of astrocytoma, the level of AQP4 is also increased. The migration ability of astrocytoma is increased along with the increasing level of AQP4.