Capital structure is the key to ensuring sufficient funding and achieving Public Private Partnership (PPP) project objectives. In Indonesia, this scheme has attracted a lot of attention to meet the enormous demand for infrastructure development. However, the successful implementation of PPP projects is often impeded by significant capital investments and high uncertainty. Improper capital structure causes many projects to fail. Therefore, to overcome these challenges, this study aims to identify the success factors for an effective capital structure for PPP projects from several leading academic journals. This study shows that Financial Viability, Business Risk, Project Participants, Country Risk Factors and Government Support are the main factors that become the basis for effective decision-making in determining the capital structure of infrastructure projects with PPP schemes. From the results of the critical success factors obtained in this study, a comparison was attempted with the implementation of fulfilling the capital structure in one of the largest PPP projects in Indonesia, namely the Trans Sumatera Toll Road (TSTR) project. The parties involved in the PPP implementation are expected to know the success factors of the capital structure so that PPP development can be carried out properly.