Abstract: Objective To explore that transforming growth factor-β induced gene (TGFBI) inhibits NCI-H28 growth in vitro. Methods TGFBI was stably transfected into mesothelioma cell line NCI-H28. growth curve, cell proliferation, platting effi ciency, and colony formation in soft agar were analyzed. Results Exogenous TGFBI in malignant mesothelioma NCI-H28 had a high expression in stably. After exogenous TGFBI transferred into tumor cells NCI-H28, doubling time of TGFBI high expression cell was increased by 4.38 times, compared with the empty vector. Relative plating effi ciency of NCI-H28 was decreased by 69.68%. T28 cells with exogenous TGFBI formed a smaller soft agar; TGFBI made tumor cells arrest in G1 phase and delay tumor cells into the S phase . Conclusion TGFBI was able to inhibit the cell proliferation of malignant mesothelioma in vitro.