The upregulation of bone morphogenetic protein and activin membrane‑bound inhibitor (BAMBI) has been observed in several types of malignant cancer, including thyroid, ovarian, liver and colorectal cancer. However, the pathological role and the regulatory mechanism of BAMBI in gastric cancer remain to be elucidated. The present study revealed that the expression of BAMBI was upregulated in gastric cancer tissue, and was correlated with tumor metastasis, disease recurrence and low survival rates in patients. Knockdown of BAMBI in aggressive gastric cancer cell lines significantly inhibited their malignant behavior, including invitro invasion and cell proliferation. β‑catenin expression was downregulated as a result of knocking down of BAMBI, and TGF-β was downregulated in a similar manner. These results demonstrated the association between BAMBI expression and gastric cancer progression, and indicate a promising direction for developing novel strategies to improve the prognosis and therapy of gastric cancer.