Objective: To investigate the expression and correlations of Oct4 and TGF-β signaling pathway related factors in gastric cancer. Methods: Western blotting was used to detect the expression of Oct4, E-Cadherin and TGF-β signaling pathway related factors TβRⅡ, Smad2, Smad3 protein in 57 cases of gastric cancer and normal gastric tissue; as well as the relationships between above-mentioned factors and clinicopathologic feature of gastric cancer, and the correlations between Oct4 expression and TGF-β signaling pathway related factors were also analyzed. Results: Compared with normal gastric tissue, the Oct4 expression in gastric cancer increased obviously, while the TβRⅡ, Smad2, Smad3, E-Cadherin expression decreased obviously (P<0.05). In gastric cancer, the expression of Oct4, TβRⅡ, Smad2, Smad3, E-Cadherin were related to tumour tissue typing, clinical stage, lymph node metastasis and serosal invasion (P<0.05). In gastric cancer, the Oct4 expression was negatively related to TβRⅡ, Smad2, Smad3 and E-Cadherin (r=-0.887, -0.912, -0.779, -0.879, P<0.01). Conclusions: High expression of Oct4 in gastric cancer may be involved in the development, invasion and metastasis of gastric cancer. The mechanisms may be related to induced epithelial mesenchymal transition by regulating TGF-β signaling pathway.