To decrease the water content of a garbage to a value suitable for an aerobic fermentation by only wringing, not requiring a big scale institution.

A garbage storing device E is provided with a turnable support member 5 supported through plural wheels 6 to a circular ring shape rail 7 laid on a stand 8, a first storing tank, second storing tank 2, third storing tank 3 and fourth storing tank arranged while adjoining mutually along a periphery direction around the turning center axis line so as to turn with the support member 5 integrally and a turning drive mechanism 13 for positioning respective storing tanks to a throw in position for throwing in the garbage in turn and a discharge position for discharging a rotten garbage at a prescribed period by turning the first - fourth storing tanks by a prescribed tuning angle intermittently.