To evaluate the cell growth inhibition and apoptosis induced by mung bean BBI in A549，we used MTT assay to detect the effect of BBI on cell proliferation. The cell apoptosis was measured by flow cytometer and the morphological changes were observed under microscope. We applied Western-Blot to test the expression level of Caspase3. The results showed that Mung bean BBI could inhibit the cell proliferation of A549.BBI could induce apoptotic changes in A549, such as chromatin condensation and the development of apoptosis bodies. The results indicated that Mung bean BBI could inhibit cell proliferation and induce apoptosis in A549.This provides experimental basis for antitumor activity of BBI.