The practice and development of PPP pattern in China are being faced with different kinds of investment risks. It’s therefore of significance to utilize legal regulation to resolve the risk problems in the operation of PPP pattern. Aiming at main investment risks consist of financing risk, operation risk, political risk and breaching risk under PPP pattern, this expounds comprehensively the legal regulation for prevention and solution of investment risks of PPP pattern from aspects of three mechanism as allocation, control and treatment. Keywords: PPP pattern; investment risk; allocation of risk; treatment of risk; legal regulation