Abstract: Objective To investigate the relationship between serum long non-coding RNA （lncRNA） H19 levels and chemosensitivity to paclitaxel-based chemotherapy in advanced gastric cancer. Methods From June 2014 to June 2016， 73 patients with advanced gastric cancer receiving paclitaxel-based chemotherapy were collected. Serum samples were collected and the levels of H19 were detected by real-time quantitative PCR （QPCR）. The relationship between serum H19 levels and clinicopathological features （sex， age， ECOG score， tumor site， differentiation and pathological type） in patients with gastric cancer were analyzed. The RECIST 1.1 version was used to evaluate the efficacy， and progression-free survival （PFS） and overall survival （OS） were investigated during the follow-up. We further analyzed the relationship between the serum level of H19 and the short-term efficacy and prognosis in patients with gastric cancer. Serum samples from 81 healthy subjects were selected as controls. The receiver operating characteristic curve （ROC） was used to evaluate the predictive value of serum H19 levels in the response of gastric cancer to paclitaxel-based chemotherapy. Results QPCR detection showed that the serum H19 levels of 73 patients with gastric cancer were 3.022±0.210， higher than 1.193±0.082 of 81 healthy subjects， and the difference was statistically significant （P<0.05）. The serum H19 levels were independent from ECOG score， age， gender， tumor location and pathological types， but related with the degree of differentiation. The serum H19 level of patients with low differentiation was 3.923±0.254， higher than 1.732±0.188 of patients with high differentiation， and the difference was statistically significant （P<0.05）. In this study， 73 cases were treated with chemotherapy for more than 2 cycles，and the short-term efficacy was evaluated. The serum level of H19 in 27 cases with chemotherapy sensitivity was 1.683±0.166， which was lower than 3.809±0.256 of chemotherapy resistance in 46 patients， and the difference was statistically significant （P<0.05）. ROC curve analysis showed that the area of serum H19 was 0.982 （95%CI： 0.966-0.998）in the prediction of gastric cancer response to different paclitaxel regimens. By the end of the follow-up period， the median PFS of 73 patients was 6.2 months and the median OS was 10.6 months. The patients were divided into high-level group （＞2.550） and low-level group （less than 2.550）， in which medium PFS of a low-level group was 7.2 months， higher than 5.3 months of high-level group （P<0.05）. There were no significant differences between different levels of H19 in term of OS. Conclusion The serum levels of H19 in patients with advanced gastric cancer were elevated and related to the sensitivity and PFS of paclitaxel containing regimen. Thus， the PFS and prognosis of the patients with lower levels were better.