ABSTRACT Objective To investigate whether ultrasound combined with microbubbles and carboplatin can induce apoptosis of human lung cancer A549 cell line. Methods The control group, US group, USMB group, CBP group, CBP + US group and CBP + USMB group were set, in which carboplatin was used at an optimal dose of 50 μg/ml, ultrasound irradiation was used at an optimal intensity of 0.6 W / cm2, and irradiation time was 60s. After 24 hours of treatment, the cells in each group were collected. FITC-labeled Annexin-V was added for 30 minutes, and then PI was added to protect from light for 5 minutes. Then, flow cytometry was applied. The apoptosis rate of A549 cells was detected. The SPSS 26.0 software was used to analyze the apoptosis rate of each group. Results The total apoptosis rate was ranked as CBP+USMB group>CBP+US group>CBP group>USMB group>US group. There was no significant difference in the early apoptosis rate between the CBP + US and CBP groups (P=0.964). The early apoptosis rates were significantly different between the CBP + USMB group and the CBP group or the CBP + US group (all P < 0.01). Pairwise comparison showed that there were significant differences in the late and total apoptosis rates among the CBP + US, CBP + USMB, and CBP groups (all P<0.01). Conclusion US or USMB combined with carboplatin chemotherapy can synergistically induce the apoptosis of A549 cells.