The oxygen deficient compound of Sr₃Fe₂O_(7-χ) phase was prepared by controlling the oxygen pressure and temperature. The lattice constants, magnetic properties and Mo¨ssbauer effects were investigated. Although the phase of Sr₃Fe₂O-(7-χ) was single phase under 10-15-300 atmosphere of oxygen pressure, variation in magnetic properties and Mo¨ssbauer effects were found dependent upon the oxygen contents.