The effect of Mg addition to PtSnNa/ZSM-5 on the catalytic properties in propane dehydrogenation was investigated. The catalysts were characterized by using different techniques: XRD, BET, TEM, NH3-TPD, XPS, TPO, and TG-DTA. Results indicate that the presence of magnesium not only modifies the acid funcfion and the structure of metallic phase but also diminishes carbon deposition on the catalyst. Among the catalysts studied, the PtSnNaMg(0.5%)/ZSM-5 exhibits the best performance in terms of propane conversion and stability. The high catalytic performance may be due to the strong interaction between Pt and Sri.