Abstract: Abstract：Objective To investigate Bax expression and the apoptosis of H460 cell induced by recombined plasmid pGL3/EGR1-Bax combined with radiotherapy in lung cancer. Methods Lung cancer cell line H460 was transfected with pGL3/EGR1-Bax plasmids and irradiated in groups. Bax expression was detected by RT-PCR and Western blot. The apoptosis of H460 cell was detected by flow cytometry. Results Restriction enzyme digestion showed pGL3/EGR1-Bax was correctly constructed. Gene-radiotherapy could significantly enhance the expression of Bax gene and protein in H460 cells (P < 0.01,compared with the control group;P< 0.05, compared with the empty vector irradiation group). The apoptosis of H460 cell in pGL3/EGR1-Bax gene therapy plus irradiation group was higher than that in either plasmid or irradiation group alone (P<0.05). Conclusion Irradiation could induce Bax expression in pGL3/EGR1-Bax plasmid in H460 cells, to significantly enhance the apoptosis of H460 cells, which may establish important experimental basis for generadiotherapy for lung cancer.