Fe2SeS is successfully synthesized by facile solid-state reaction and the electrochemical investigation of Fe2SeS as anode for lithium ion batteries is reported for the first time. Fe2SeS deliverers a large initial discharge capacity of 471 mAh g−1. The initial coulombic efficiency (92.56%) is higher than most of double-anion compounds reported previously. It is unexpected to find that Fe reacts simultaneously with Li2S and Li2Se to reform Fe2SeS during charging process, which is different from most double-anion compounds.