Abstract: Objective: To detect the abnormal promoter methylation of p14^ARF，p16^INK4a，O⁶-methylguanine-DNA methyltransferase (MGMT)，glutathione S-transferase P1(GSTP1)，BUB3 and death-associated protein kinase (DAPK) genes in the transformed human bronchial epithelial cells (BEP2D) induced byα-particles.Methods: Abnormal promoter methylations were detected with methylation specific PCR(MSP)；The level of p14^ARF gene transcription was analyzed using RT-PCR.Results: p14^ARF gene was not methylated in BEP2D cells，but was methylated in the malignant transformed BERP35T-1cells， and the level of its transcription was depressed remarkably in the latter.However p16^INK4a gene，which shares two exons with p14^ARF gene， was not methylated.MGMT gene was methylated in both BEP2D and BERP35T-1.DAPK gene was partially methylated in BEP2D cells and methylated completely in BERP35T1.GSTP1 was not methylated in BEP2D cells and was methylated partly in BERP35T-1.BUB3 gene was not methylated in BEP2D as well as BERP35T1 cells and this was further proved by sequencing analysis.Conclusion: Some of the genes which play important roles in cell proliferation，DNA repair and apoptosis were methylated in the transformed human bronchial epithelial cells induced byα-particles.