Objective To investigate the effect of knocking down LncRNA TCONS-00022381 on apoptosis of human gastric cancer cells MKN45. Methods Culturing Human gastric cancer MKN45 cells and dividing them into three groups. Cells in each group were transfected using the Liposome transfection method, the siRNA targrting LncRNA TCONS-00022381 was transfected into the si-TCONS group, the negative siRNA was transfected into the NC group, and the Blank group was cultured in routine. The cell viability of each group was measured after 24h, 48h, and 72h of transfection using the CCK8 assay TCONS knockdown efficiency was detected by RTqPCR after 24h of transfection. The expression of Bcl-2 and Bax was detected by western blotting after 48h hours of transfection. The apoptotic rate of cells was detected by flow cytometry after 48h of transfection. Results The siRNA targeting LncRNA TCONS-00022381 significantly inhibited its expression in MKN45 cells (P<0.001). Compared with the Blank group and the NC group, the viability of MKN45 cell in the si-TCONS group decreased significantly (P<0.001). The expression of Bcl-2 was significantly down-regulated (P<0.01). The expression of Bax was significantly up-regulated (P<0.01). The rate of cell apoptosis increased significantly (P<0.05). Conclusion Knock down of LncRNA TCONS-00022381 may promote the apoptosis of MKN45 cells by regulating the expression of Bcl-2 and Bax.