The main purpose of this paper is to investigate the non-linear impact of globalization on life expectancy in Iran during 1979-2014. For this purpose, I use the smooth transition regression (STR), model. The estimated Smooth Transition Regression (STR) model supports a nonlinear threshold behavior in the relationship between globalization and life expectancy in the country in a two-regime structure with a positive effect and a threshold level of about 38.26%. So with crossing over the threshold level and entering the second regime the intensity of this positive impact would be increased. Accordingly, it can be said that the globalization plays an important role in increasing life expectancy in Iran.