Through-silicon-via (TSV) is one of the major design techniques in three- dimensional integrated circuit (3D IC). Based on the parasitic parameter extraction model, the parasitic resistance-capacitance (RC) parameters for different size TSVs are acquired and validated with Q3D simulation data. Using the results of this model, closed-form delay and power consumption expressions for buffered interconnect used in 3D IC are presented. Comparative results with 3D net without TSV in various cases show that TSV RC effect has a huge influence on delay and power of 3D IC, which leads maximum delay and power comsumption to extra increase 10% and 21\% on average, respectively. It is crucial to correctly establish a TSV-aware 3D interconnect model in 3D IC front-end design.