〔Abstract〕 Objective To compare different effects of sodium butyrate, Hemin and DMSO on erythroid differentiation of K562 cells.Methods K562 cells were treated with 1.5 mmol/L sodium butyrate, 20 μmol/L Hemin and 2% DMSO for 120 h and the medium of K562 was changed every 24 h. The changes of cell counts,cell cycle,the positive rate of TMB and the expression of CD235 a were detected. Results Proliferation of K562 was inhibited in G0/G1 from 48 h to 72 h and G2/M phase from 96 h to 120 h by sodium butyrate,and the positive rate of TMB was( 22. 02 ± 2. 27) % at 120 h. Hemin had no statistical significance on the proliferation and cell cycle of K562,and the positive rate of TMB was( 90. 83 ± 2. 69) % at 120 h. The proportion of G0/G1 of K562 treated with DMSO increased,but there was no statistical significance on cell proliferation after 72 h culture,and the positive rate of TMB was( 1. 84 ± 0. 48) %,which was not significantly different from that of the control group( 2. 89 ± 0. 18) %.The level of CD235 a of K562 exposed to sodium butyrate and Hemin improved compared with control group and DMSO group after cultured 120 h and there was no statistical significance between two groups. However,there was no statistical significance between the expression of CD235 a of the DMSO group and the control group. Conclusion According to the comparison the changes of proliferation,cell cycle,positive rate of TMB and expression of CD235 a of K562 after erythorid induction,it is found that Hemin is a more effective reagent than DMSO and sodium butyrate in inducing erythroid differentiation of K562.