This paper evaluates the effect of the BRI on the high-tech products export to China by using the difference-in-differences method. The results show that BRI has significantly increased the high-tech product export of the countries along the route to China, which is confirmed by a series of effectiveness and robustness tests. The heterogeneous effect analysis suggests that geographically, the countries along the Land Silk Road, far from China and with the comparatively perfect institution is strongly promoted. We also explore the heterogeneous effect at the products levels by using triple difference models,which indicates that the effect is mainly concentrated on the mid products. The positive effect of the BRI can be realized and explained through the five connectivities, which promote the development of infrastructure, financial market and technology of the countries along the route.In addition, the effect of the BRI is manifested by the expansion of the intensive margin and extensive margin,which means the variety and the average of high-tech products of the countries along the route exporting to China are increased.