This paper discusses the application of digital design in foreign aid projects, focusing on the use of BIM technology. Through literature review and case analysis, the study reveals that digital design offers significant benefits in pre-project planning comparison, construction simulation, and green building performance analysis. Digital design through BIM integration technology enables unified data management and efficient information sharing, thereby enhancing the efficiency of project collaboration and transmission between domestic and international stakeholders. The BIM integration and application of the Belarus International Standard Swimming Pool Project constructed by Beijing Construction Engineering exemplifies the critical role of digital design in foreign aid projects and provides valuable guidance for BIM technology application in "Belt and Road" foreign aid initiatives.