Objective To investigate the effect of different concentrations of raloxifene (RAL) on the proliferation and apoptosis of human aortic valve interstitial cells (AVICs) in vitro. Methods AVICs were isolated from human aortic valve by collagenase type Ⅱ, and cultured in different concentrations (0 nmol/L, 0.1 nmol/L, 1 nmol/L,10 nmol/L, 100 nmol/L and 1 000 nmol/L) of RAL. AVICs cultured in 0 nmol/L RAL were treated as the control group and those in other concentrations of RAL as the experiment groups. The proliferation and apoptosis of AVICs were evaluated by Cell Proliferation Assay (MTS assay) on day 0, 3, 5, 7 and 9. Flow cytometry was used to detect the cell cycle and apoptosis of AVICs on day 7. Results MTS results showed that the optical density value at 490 nm was much less in 10 nmol/L RAL and 100 nmol/L RAL groups (P<0.05) on day 5, 7 and 9 than that in the control group. Flow cytometry results demonstrated that S-phase rate (P<0.05) and cell apoptosis rate (P<0.05) on day 7 were lower in the 10 nmol/L and 100 nmol/L RAL groups compared with the control group. Conclusion RAL with suitable concentration can inhibit proliferation and apoptosis of AVICs, which will lay an important foundation for further research of the role of RAL on heart valve diseases.