Objective: To investigate the expression of troponin T1(TNNT1) in clinical gastric cancer tissue samples and gastric cancer cell line HGC-27. Methods : The expression of TNNT1 protein in gastric cancer tissues was analyzed using the UALCAN and GEPIA databases to assess its differential expression. Western blot was used to detect the protein expression in clinical samples of gastric cancer tissue. The effects of TNNT1 protein on proliferation, invasion and migration of gastric cancer cell HGC-27 and relationship with clinicopathological features of patients were quantitatively detected and analyzed by MTT and Transwell assays. Results: The expression of TNNT1 protein was up-regulated in HGC-27 cells. The expression of TNNT1 protein was down-regulated(P<0.01) and the proliferation, invasion, migration of HGC-27 cells were inhibited(P<0.01) after transfection with sh-TNNT1. The expression of TNNT1 protein was down-regulated in gastric cancer tissues and correlated with TNM stage(P=0.049) and depth of tumor invasion(P=0.011); There was no significant correlation with patient age, tumor diameter, lymph node metastasis, and tumor differentiation. Conclusion Down-regulating of TNNT1 protein expression can inhibit the proliferation, invasion and migration of gastric cancer cells HGC-27.