Objective    To study the effect of Apg-2 on H

2

O

2

-induced damage to Bcr/Abl positive BaF3-P210 cells.     Methods    Damage models of BaF3-MIGR1 cells infected with pMIGR1 vector and BaF3-P210 cells stably expressing Bcr/Abl were induced by H

2

O

2

. Expression of

Apg-2 in the two models was detected by Western blotting and RT-PCR. Damage models of BaF3-MIGR1 and BaF3-P210 cells with overexpressed Apg-2 were also induced by H

2

O

2

. Expression of phosphorylated histone （γ-H

2

AX） and its focal points was detected by Western blotting and immunofluorescence

respectively.     Results    The expression levels of Apg-2 protein and mRNA in BaF3-MIGR1 and BaF3-P210 cells were increased when Apg-2 was exposed to H

2

O

2

（P0.05）. The expression levels of  γ-H

2

AX and its focal points in BaF3-MIGR1 and BaF3-P210-Apg 2 cells were also increased after treatment with H

2

O

2

（P＜0.05）. However

no significant alternation was observed in expression of  γ-H

2

AX in BaF3-P210 and BaF3-P210-Apg2 cells after treatment with H

2

O

2

.     Conclusion    Apg-2 can reduce H

2

O

2

-induced expression of γ-H

2

AX in BaF3-P210 cells

thus decreasing cell damage.