OBJECTIVE To study the effects of elemene (Ele) on proliferation and cell cycle of human lens epithelial cells B3 (HLE-B3) and the mechanisms of its signal transduction. METHODS Recombinant human basic fibroblast growth factor (rhbFGF) was used to induce proliferation of HLE-B3 cells, which were incubated with 80mg/L Ele for 24 hours. The inhibitory effects of Ele on the proliferation of HLE-B3 cells were evaluated by MTT method. The effect of Ele on HLE-B3 cell cycle was analyzed by flow cytometry(FCM). The expressions of protein kinase A (PKA) and protein kinase G (PKG) of HLE-B3 were also analyzed by FCM. RESULTS Ele altered the cell cycle of HLE-B3 and effectively inhibited HLE-B3 cell proliferation induced by rhbFGF. Ele up-regulated PKA and down-regulated the expression of PKG in HLE-B3 cell. CONCLUSIONS Ele inhibits HLE-B3 proliferation, making it an attractive potential agent in regimens to treat after-cataracts.