Project financing of ESCO is the key link to conduct EEEB. The more scientific project financing strategies are affected by some inner factors, such as financial situations in a corporation and corporate business objectives, and involved by some external factors, such as project status, marketing character of energy saving service market and constraints by policy and law. From the analysis on reciprocal action between inner and external factors, financing cost, financing risk and income from investment are the three main factors to choose an appropriate financing mode. ESCO can implement project financing by enhancing enterprise competitiveness, improving the market climate and fostering a normative policy and law environment.