Critical illness insurance is the best combination of commercial insurance participation in social medical insurance which is known as an innovative way to resolve long standing “proper health care is difficult to get” and “proper health care is expensive”. problems in China. The stability and sustainability of critical illness insurance depends on current and mediumterm balance of payments of insurance funds. Since the implementation of critical illness insurance in H Province，the preliminary security effect has been shown up，which is reflected in the clear alleviation of the medical expenses of the insured. But in the long run,both urban and rural residents’ health insurance funds are facing a financial crisis of balance of payments. Therefore,it is necessary to enhance the participation enthusiasm of commercial insurance institutions,increase government investment and policy support,build a multichannel financing system for critical illness insurance,and strengthen the dynamic supervision of critical illness insurance funds. In this way,we can ensure the basic balance of payment of the insurance funds and provide strong support and reliable guarantee for the sustainable operation of the critical illness insurance system.