Abstract: 【Objective】To investigate the effects of insulin-like growth factor 1 (IGF1)on the proliferation of antler organic center cells from various passages in vitro at 60 days growing period of antler. 【Method】Antler organic center cells were isolated from sika deer antler of growing 60 day and cultured. The second, fifth and eighth population cells were incubated with 0, 1, 3, and 10 nM IGF1. Thymidine incorporation assay was applied after 24 hours of culture respectively to determine the disintegration per minute ( DPM) value.【Results】The proliferation of cells from growing 60 day’s antler in the experimental groupwas significantly higher than that of the control group (p<0.01). The average and maximal DPM value of the proliferation of cells in the experimental group was the highest in the second population cells (31918 and 39818 DPM/mg respectively), decreased in the fifth population cells materially (5455 and 6815 DPM/mg), and decreased in the eighth population cells again (4030 and 4838 DPM/mg). 【Conclusion】The results show that IGF1 can enhance the proliferation of antler organic center cells cultured in vitro. The sensitivity of IGF1 on the antler organic center cells from various passages at 60 days growing period of antler in vitro.