Abstract: 　Objective　To investigate the effects of matrine on the proliferation and apoptosis of SK-NEP-1 cells in vitro,and its possible mechanism. Methods Trials were divided into following groups: control group, 0.5, 1.0 and 1.5mg/ml of matrine intervention groups. The inhibition rate of SK-NEP-1 cells treated with different concentration of Matrine was detected by MTT colorimetric assay. Apoptosis rate was detected by flow cytometry (FCM). RT-PCR analysis was employed to measure the PDCD4 mRNA expression. Results Matrine (final concentrations=0.5, 1.0 and 1.5mg/ml) could induce apoptosis and inhibit the growth of SK-NEP-1 cells. Compared with the controls without matrine treatment (8.81±3.71) %, the inhibition rates of SK-NEP-1 cells were (20.79±6.20)%, (31.25±5.07)%, and (51.15±12.70)%, respectively; the apoptotic rates of SK-NEP-1 cells treated with different concentration of matrine were (13.67±0.78)%,(17.43±1.65)% and (20.80±1.54)%, respectively. Significant difference in the inhibition and apoptotic rates of SK-NEP-1 cells between each drug group and control group was observed(P<0.05), and the inhibition and apoptotic rates of SK-NEP-1 cells increased gradually with increased matrine concentration, thus exhibiting a dose-dependent effect （P<0.05）. To the expression of CXCR4 mRNA，the grey levels of SK-NEP-1 cells treated with matrine intervention group (final concentrations=0.5, 1.0 and 1.5 mg/ml) were (0.720±0.058), (0.540±0.095) and (0.307±0.050), respectively. The mRNA expression of CXCR4 was seen in SK-NEP-1 cells. Compared with control group, the expression of CXCR4 mRNA was decreased significantly in matrine intervention group (P<0.01).There were significant difference in CXCR4 mRNA level among the SK-NEP-1 cells treated with 0.5,1.0,1.5mg/mL of matrine (P<0.01). Conclusion Matrine could induce apoptosis and inhibit the growth of SK-NEP-1 cells in a dose-dependent way which may be associated with the down-regulated CXCR4 expression in SK-NEP-1 cells.