A new method for optimally allocating superconducting fault current limiters（SFCLs） is presented. By calculating short circuit， the branches with SFCLs capable of starting up reliably can be determined. Subsequently， by analyzing the influences of SFCLs on impedance matrix， sensitivities of the self-impedance of over-standard substations with respect to impedances of these branches are obtained. Based on the sensitivity values， a few candidate branches can be chosen from these branches. Finally， by using multi-objective optimization algorithm called non-dominated sorting genetic algorithm-Ⅱ（NSGA-Ⅱ）， these candidate branches can be optimized， and thus searching for the optimal location and the smallest SFCLs capacity can be achieved. Simulation results of a 6-bus system and the IEEE 39-bus system are employed to verify the effectiveness and reliability of the proposed method， respectively. With the proposed method the searching space of solutions can be greatly reduced. The optimal allocation of SFCLs is realized and the short circuit current of over-standard substations is restrained successfully.