Objective: To explore the effect of cryoablation on apoptosis of lung adenocarcinoma cells. Methods: According to the district in the tumor following cryoablation, human lung adenocarcinoma H1299 cells were divided into four groups to construct the freezing model of lung cancer in cell level: group A, untreated cells, as the control group. In group B, the necrotic solution was added to the untreated cell culture medium(the cell suspension was frozen in a liquid nitrogen tank for 5 min, and centrifuged to obtain the supernatant after rewarming at 37 ℃).Group C, sublethal cells(cells were frozen at-80 ℃ for 7 min to mimic sublethal state). In group D, necrotic solution was added into sublethal cell culture medium. Cell apoptosis was observed by flow cytometry analysis 24 h later. The expression of apoptosis related molecules Bax and Bcl-2 was detected by qRT-PCR and Western blot. Lewis lung adenocarcinoma cell line was used to establish subcutaneous transplanted tumor model of C57 BL/6 mice. The successful model mice were randomly divided into two groups: sham operation group and argon-helium cryoablation group, with 4 mice in each group. After argon-helium cryoablation for 14 days, the tumor tissues were taken. The expression of apoptosis-related molecules Bax and Bcl-2 was detected by qRT-PCR and Western blot. Results: In the cell freezing model, compared with group A in the control group B,C and D groups could promote cell apoptosis(P<0.05), and group D had the highest apoptosis rate, which was significantly higher than other groups(P<0.05). Bothin vitroandin vivoexperiments showed that cryoablation could increase the expression of Bax mRNA and protein(P<0.05). Bcl-2 mRNA and protein expression decreasedin vivo(P<0.05). There was no significant change in the in cell freezing model. Conclusion Cryoablation can achieve effective ablation through cell apoptosis mechanism, which may be related to the reduction of Bcl-2/Bax.