This study examines the association between the Belt and Road Initiative (BRI) and export variety (EV). We propose three hypotheses on how BRI may foster export markets (destinations) or export product lines. The estimates are based on a dataset constructed specifically for this analysis, covering 183 countries and linked with trade data from 1996 to 2019. We apply the instrumental variable (IV) approach in regressions for covering the endogeneity. The results indicate that participation in BRI is negatively related to EV. Specifically, we find evidence that, on average, BRI participants have less EV (by product and by destination) and greater export concentration. As regards participation in the Asian Infrastructure Investment Bank and BRI meanwhile (AIIB_BRI and AIIB_MOU), the results show a more negative effect. And there are heterogeneous effects of BRI across different economies and sectors.