This paper examines causal relationships between economic globalization, the three indices for product diversification of exports (Theil index, intensive margin and extensive margin) and economic growth in the unbalanced panel data framework in 139 countries over the period 1970-2010. We also consider the subgroup of the countries related to the income levels and run the panel Granger non-causality tests for heterogeneous panels. The empirical results indicate that there is a bidirectional causal relationship between economic globalization and economic growth. There is also a significant causal relationship that runs from all three indices for the diversification of exports to economic growth. After implementing various robustness checks, we observe that diversification of exports and economic globalization are positively related with economic growth merely in the upper middle economies.