Abstract: Objective To investigate the level of microRNA-7 （miR-7） and its clinical significance in advanced gastric cancer. Methods The plasma samples of 75 patients with advanced gastric cancer and 73 healthy subjects were collected from June 2013 to June 2016 in this hospital. The miR-7 level was detected by quantitative real-time PCR （QPCR） technique. The relationship between plasma miR-7 levels and clinicopathological features was analyzed in patients with gastric cancer. According to the follow-up data，the relationship between plasma miR-7 level and prognosis was analyzed in patients with gastric cancer. Results The QPCR detection showed that miR-7 level was （0.351±0.258） in 75 cases of gastric cancer patients， less than （1.088±0.464） of 73 healthy subjects and the difference was statistically significant （P＜0.05）. The plasma miR-7 levels were independent of sex， age， ECOG score， tumor site and pathological type in patients with gastric cancer， but were related to the degree of differentiation. Among them， the miR-7 level of the low differentiation group was （0.254±0.155）， lower than （0.514±0.313） of the high／middle differentiation group， and the difference was statistically significant （P＜0.05）. The median progression free survival （PFS） and overall survival （OS） of 75 patients were 6.6 and 10.5 months. The median PFS of miR-7 high expression group （＞0.351） was 7.1 months， better than 5.8 months of the low expression group （≤0.351） （P＜0.05）. There was no significant difference between the two groups in OS （10.3 months vs. 10.6 months， P＞0.05）. Conclusion The plasma miR-7 level decreased in advanced gastric cancer， and patients with low miR-7 level were poorly differentiated. The PFS of a high miR-7 level is better，and the index has a good value in the prediction of prognosis on gastric cancer.