ABSTRACT [Objective] Studying the role of CircAKT3 in the proliferation and apoptosis of osteosarcoma U2OS cells, so as to investigate the effect of CircAKT3 on the biological behaviors of osteosarcoma. [Methods] qRT-PCR was used to detect the expression of CircAKT3 in osteosarcoma U2OS cells and osteoblast h FOB1.19 cells. Subsequent experiments were divided into two groups. The experimental group was transfected with SiRNA for CircAKT3, while the control group with the SiRNA control sequence. The transfection efficiency was then detected by qRT-PCR. CCK-8 assay was used to detect the optical values (OD) at 24, 48, 72 and 96 h between the two groups. The apoptosis rate of the two groups was conducted by flow cytometry. [Results] qRT-PCR results showed that the expression of CircAKT3 in the U2OS cells was significantly higher than that in the h FOB1.19 cells. The expression of CircAKT3 in the experimental group was significantly lower than that in the control group 24 hours after SiRNA transfection. Results of CCK-8 assay showed that the OD values of the experimental group at 24 and 48 h were not significantly different from those of the control group, while the OD values at 72 and 96 h were significantly lower than those of the control group. Results of flow cytometry showed that the apoptosis rate of cells in the experimental group (11.572.82)% was significantly higher than that in the control group (2.211.17)%. [Conclution] CircAKT3 can promote the proliferation of U2OS cells and inhibit the cell apoptosis.