In the context of a focus exploiting for alternative and renewable energies to reach the emission reduction goal in China, wind power industry serves as a significant development object and also shows vast development space. However, for its investors, project risks and the long-term positive trend are coexistent, due to the joint influence of several factors as the result of Chinese wind power industry circumstance and relative policies and regulations, such as investment in construction period, cost in operation period, electricity connected to grid, feed-in tariff, CDM project income, and government subsidy. To assess the investment risk of wind power project, this paper constructed a process which initially simulated NPV with Monte Carlo method and then analyzed the investment payback period as well as IRR based on it. Next, combining with a specific case in north China, firstly the credibility and accuracy of proposed simulation process were verified, then the NPV was simulated and the investment payback periods as well as IRR were evaluated under different grid-connected ratios in two conditions, namely the project with and without CDM income. The simulation results indicated the proposed case having high investment risk, so afterward general suggestions on mitigating the investment risks of wind power project in China were presented. Crown Copyright (C) 2012 Published by Elsevier Ltd. All rights reserved.