The article explores how risk factors impact public-private partnership transportation projects in Vietnam. By analyzing critical risk factors through literature review, expert interviews, and case studies, the researchers identified key obstacles for private investors. These include issues with acquisition/compensation, approvals, feasibility studies, finance, evaluation methods, and laws/regulations. These risks were grouped into categories like bidding process, finance, laws/regulations, and project evaluation. Addressing these challenges is crucial for attracting private investors to Vietnam's PPP projects.