With shrinking process size, many variations have a growing impact on circuit performance for today’s integrated circuit(IC) technologies. In this paper, we describe a high-order model of circuit performance analysis under time-space variations. The time-space variations, such as process variations, place and route imformance, environment parameters and temporal variations, are included in hierarachical perfornance analysis. The time-space variations are increased in variance analysis. Based on quadratic model, coefficients of the K-L expansion and function item are decided. The high-order analysis model is built. The result of experiment proves that the proposed method can improve analysis performance effectively.