A method for absorbing and releasing hydrogen comprises applying repeatedly hydrogen pressurization and depressurization to a hydrogen storage metal alloy of a body-centered cubic structure-type phase exerting a two-stage or inclined plateau characteristic in a hydrogen storage amount vs hydrogen pressure relation in an appropriate fashion to absorb and release hydrogen. At least at one stage during the release of hydrogen, the temperature (T2) of the above-mentioned hydrogen storage metal alloy is made higher than the temperature (T1) of the hydrogen storage metal alloy during the hydrogen absorption process (T2>T1). This enables the release and utilization of occluded hydrogen at a low-pressure plateau region or an inclined plateau lower region.