This article provides an empirical analysis of the relationship between research and development (R&D) expenditures and economic growth, and determines whether this relationship differs with respect to the degree of development. In this regard, the study utilises data from 52 countries from 1996 to 2010 and employs a dynamic panel data model. The research finds that R&D expenditure has a positive and significant effect on economic growth for all countries in the long run, which is consistent with the relevant literature. For developing countries, the effect is weak in the short run but strong in the long run, as expected. The study adds new empirical evidence to the literature.