Solid Oxide Fuel Cell(SOFC) is a high efficiency, environmental friendly energy exchange equipment . Interconnect  is one of the necessary components in SOFC. However, the Cr evaporate from interconnect may react with cathode material and lead to severe degradation of SOFCs. This study demonstrate the significant effect of Cr- poisoning on the performance of Sm_xSr_1-xMnO₃(SSM) cathode. After 200h long-term aged with Cr at open circuit potential and short term test  under cathodic current , the SSM always shows very slow Cr caused degradation rate and low polarization resistance at 750℃. This results indicate that  the SSM is a promising candidate cathode material for SOFCs. The remarkable high anti-Cr poisoning effects may ascribe to the Sm in A site of ABO₃  perovskite has smaller size which lead to  more robust bonding.