The effects of Oxymatrine (Oxy) on the proliferation and apoptosis of human esophageal carcinoma Eca109 cell line and the mechanism were investigated. The human esophageal carcinoma Eca109 cells were cultured in vitro. The Oxy-induced apoptosis of Eca 109 cells was assayed by using flow cytometry. The expressions of p-ERK1/2, Cyclin D1, p21waf/cip1, Bax and Bcl-2 were detected by Western blot. Flow cytometry revealed that Oxy could induce the apoptosis of Eca109 cells. Western blot showed that Oxy of different concentrations suppressed the expressions of p-ERK1/2, Cyclin D1 and Bcl-2, but up-regulated the expression of p21waf/cip1 and Bax, and the ratio of Bax/Bcl-2 was increased. It was suggested the Oxy could induce the apoptosis of Eca109 cells, which might be related to the upregulation of p21waf/cip1 and the downregulation of p-ERK1/2, Cyclin D1 and p21waf/cip1. The possible pathway may be related to Bcl-2/Bax.