Even though the operation temperature of solid oxide fuel cells (SOFCs) stacks has been reduced (w750 C), stainless steel interconnect within the stacks still requires protection by high conductive coatings to delay the growth of oxide scales and reduce chromium evaporation. Manganese cobaltite spinel protective coating with a nominal composition of MnCo 2 O 4 was produced on Fee21Cr stainless steel. Electrical, microstructural and compositional analysis were performed to investigate the interfacial reaction of MnCo 2 O 4 protective coating with the stainless steel substrate during 750 C oxidation process. The spinel coating not only acts as a barrier to Cr outward transport, but also improves the electrical conductivity of the alloy interconnect during long-term oxidation. The coated alloy demonstrates good electrical conductivity with an area specific resistance (ASR) of about 5 mOhm cm 2 after oxidation for 1000 h at 750 C, which is about 1/4 of the ASR of bare Fee21Cr alloy. The reduction of ASR might be caused by the fact that Cr migrated from the steel substrate interact with MnCo 2 O 4 coating and generated MneCoeCr spinel phase, which has higher electrical conductivity than that of Cr 2 O 3 .