Objective:To investigate the effects of 2-Deoxy- D-glucose (2-DG) on the cell cycle and apoptosis of human esophageal cancer(EC) Eca109 cells. Methods:At two different levels of O2(19% and 1%),treating with various concentrations (0,5,10, 20,40,80 mmol/L) of 2-DG for 24 h,the cell cycle and apoptosis were detected by flow cytometry. Results:After treatment with 2-DG at concentrations of 0 and 80 mmol/L 2-DG for 24 h,the proportion of G1 phase cells under 19% level of O2 were (44.87 ± 0.99)% and (64.60 ± 2.17)%,the apoptotic Eca109 cells reached (3.90 ± 1.61)% and (7.23 ± 1.43)%,respectively. While at 1% O2 level,the proportion of G1 phase cells were (54.23 ± 1.42)% and (87.74 ± 2.19)% (P < 0.05),and the apoptotic Eca109 cells reached (38.02 ± 1.42)% and (68.72 ± 1.47)% (P < 0.05),respectively. Conclusion:2-DG is able to significantly induce cell cycle arrest and apoptosis effectively in a dose-dependent manner, and under hypoxic conditions,Eca109 cells become more hypersensitized to 2-DG.