By drawing upon the knowledge-based view (KBV) and family business literature with a focus on socioemotional wealth (SEW) perspective, we suggest that there will be generational differences in family firms’ international diversification. We also suggest that the interaction effects of family ownership and knowledge-based resources on the international diversification in first and second generation family firms will differ. Through the longitudinal analysis of 428 S&P 500 firms, we find support for our hypotheses. Results show generational differences in international diversification among publicly-traded family firms and the impact of knowledge-based resources on these differences.