ObjectiveTo investigate the effect of frankincense on the proliferation, apoptosis and migration of human gastric cancer SGC7901 cells and the possible mechanisms. Methods After the SGC7901 cells were treated with frankincense at different doses for different time periods, the proliferation of the cells was determined by MTT assay. Flow cytometry was used to detect the apoptosis of the cells treated by 0.0,0.5,1.0,2.0,4.0 or 8.0 mg/ml frankincense for 24 h. Western blotting was employed to detect the expression of phosphatase and tensin homolgy deleted on chromosome ten(PTEN), phosphatased Akt(p-Akt), protein kinase B(PKB, also named Akt), and cyclooxygenase-2(COX-2) in the cells after frankincense treatment (0,2 and 4 mg/ml) for 24 h. Wound-healing test was performed to assess the effect of frankincense on the migration of SGC7901 cells. A xenograft nude mice model of human gastric cancer was established to evaluate the anti-cancer effect of frankincense in vivo. Graphpad Prism 6.0 software was used to perform data analysis. Results Frankincense significantly inhibited the proliferation and migration of SGC7901 cells in a dose-and time-dependent manner. It also induced the apoptosis of the cells dose-dependently. Frankincense treatment resulted in the up-regulation of PTEN and down-regulation of p-Akt and COX-2 at a protein level. It could also inhibit the tumor growth in the xenograft nude mice model of human gastric cancer. Conclusion Frankincense may inhibit the proliferation and migration and promote the apoptosis of SGC7901 cells through the PTEN/Akt/COX-2 signaling pathway.