This paper is to evaluate the optimal threshold for premium uncertainty dealt with the entry strategy in insurance industry into Mainland China's life insurance market. To price the optimal project value and to provide strategy manager for another decision way of thinking is the focal point in this paper. How to use real options approach for the entry model and to compare the differences between real options approach and risk adjusted net present value method is also mainly study in this paper. The effect for insurance industries meeting in different situations before and after Mainland China becoming a member of the World Trade Organization is discussed. When competitive firms joint into market, the existed firm promotes service quality in order to increasing or keeping the market share, and evaluates the effect on the project value under service cost input as different timing under market scale uncertainty.