By analyzing the characteristics and deficiencies of current reserve discount rate curve recommended by the CIRC for insurance contract,this paper uses the S-W model to fit the risk-free yield curve.Compares to existing method,we find that the S-W model overcomes the deficiencies of Hermite on calculating cumbersome,requiring more critical period point,cannot be extrapolated,lacking of economic significance.The S-W model not only makes the full use of market information but also perform excellent in stability and inter-temporal consistency.The SW model is well suited for the long-term bonds illiquid market such as China.