Solid oxide fuel cells (SOFCs) are expected as a next-generation energy conversion device having high efficiency. In order to improve the performance, durability and reliability of SOFCs, further understandings of the electrode reactions are necessary. For this purpose, the introduction of spectroscopic analytical techniques, combined with conventional electrochemical measurements, would be effective. In a last decade, we have been investigating the electrode reactions in SOFCs by applying the operando X-ray absorption fine structure (XAFS) measurements. In this paper, our recent research activities using operando XAFS analysis are reviewed.