As the most typical appliction of superconducting technology, superconducting fault current limiter (SFCL) can alleviate the serious situation that the short circuit current grows quickly with the expansion of power system, and ensure the stability of power grid as well as the safety of electric equipment. However, the normal operation of power system relay protection devices would be affected by the impedance characteristics of SFCL. For these problems, firstly the structure and the woking principle of saturated iron-core SFCL are introduced briefly. Then the influences of SFCL on circuit protection, distance protection, zero-phase circuit protection and longitudinal differential protection are analyzed. Finally, some corresponding solutions are proposed by modifying the setting value of protections and improving the design requirements of SFCL, These solutions provide a reference for the practical applications of SFCL.