This study aims at investigating the relationship between the degree of internationalization and firm performance in Cameroon. Based on a panel dataset of 114 firms surveyed by the World Bank from 2009 to 2019, the regression results find evidence that there exists a relationship between internationalization and performance with respect to the W-shape while the model controls the characteristics of the business environment and firm characteristics. This result has confirmed the impact of internationalization on the firm performance going through 4 stages (W-shaped). We draw a number of implications for the study of internationalization in both theory and practice.