Objective  To investigate the effects of microRNA(miR)-29a-3p on the proliferation and invasion of gastric cancer cells and analyze its related molecular mechanism.    Methods  The expression level of miR-29a-3p in gastric cancer cells was detected, and the role of miR-29a-3p in the proliferation, migration, and invasion of gastric cancer cells was evaluated. Western blotting and luciferase analysis showed that miR-29a-3p was directly bound to Serpinh1 3’-untranslated region(3’UTR). In addition, the effects of the miR-29a-3p/Serpinh1 axis on the proliferation, migration, and invasion of gastric cancer cells were detected by MTT assay, colony formation assay, and Transwell assay in vitro.   Results  After transfection, the expression of miR-29a-3p in the miR-29a-3p mimic group was significantly higher than that in the miR-29a-3p negative control and blank group. After transfection, the proliferation of BGC823 cells decreased significantly. Luciferase analysis showed that miR-29a-3p inhibited the expression of Serpinh1 by targeting the 3’UTR of Serpinh1. In addition, overexpression of miR-29a-3p significantly inhibited the proliferation, invasion, and migration of gastric cancer cells by targeting Serpinh1.  Conclusion  MiR-29a-3p can target Serpinh1 and regulate the proliferation and invasion of gastric cancer cells.