Abstract: Objective: To determine the proliferation inhibitory and apoptosis-inducing effects of cinnamaldehyde on HL-60 cells. Methods: The proliferation inhibitory effect was evaluated using trypan-blue staining and MTT assay, and the apoptosis-inducing effect using flow cytometry, scanning electron microscope (SEM) and transmission electron microscope (TEM). Results: Cinnamaldehyde had an oblivious inhibitory effect on the proliferation of HL-60 cells with dependence upon its concentration and treatment time and the LC50, median lethal concentration was 34.87 μg/mL. The rate of apoptosis in HL-60 cells was 32.6 % after being treated with cinnamaldehyde at the dose of 20  μg/mL. for 16 h. Typical apoptotic morphological changes in the cells was observed under fluorescence microscopy, SEM and TEM. Conclusion: cinnamaldehyde cna notably inhibit the proliferation and induce the apoptosis of HL-60 cells.

Key words: cinnamaldehyde, HL-60 cells, apoptosis