The development of cross-border e-commerce is generally faced with problems such as high freight, long transportation time, and low service level. However, overseas warehouses can effectively solve the above problems to a certain extent, and they can improve consumer satisfaction. Therefore, this paper proposed a method combined with the entropy technique for order of preference by similarity to ideal solution (E-TOPSIS) model and complex network analysis theory to make a comprehensive determination of overseas warehouse locations for China’s e-commerce exports in the context of the Belt and Road Initiative (B&R). We selected 62 countries along the B&R as pre-candidates for overseas warehouse locations and then evaluated the significance of each node in cross-border e-commerce for Chinese export products. Finally, 15 countries were identified as the optimal overseas warehouse locations for Chinese export products along the B&R. The results can provide reference for overseas warehouse deployment of Chinese cross-border e-commerce enterprises as well as the development and the construction of the B&R.