NOVELTY - Organic waste composting device, comprises an input hopper, crusher, input hopper, crushed material reservoir, returning unit, fermenting tank, agitating tank, maturing tank, compost reservoir, selection tank, package tank, leachate reservoir, sending unit, aeration tank, solid-liquid separation tank, and treatment tank which adds the aerobic microorganism to the separated liquid to purify it and supplies it to the fermenting tank and agitating tank.    USE - The device and method are useful for composting organic waste (all claimed), used as soil conditioner for promoting growth of crops.    ADVANTAGE - The organic waste composting device is environmentally-friendly as it does not generate bad odor and leachate. The mixing of organic waste, including waste and seed compost or excipients, or flocculant caused tangles and aggregation immiscible blends on the conveyor are prevented. The organic waste can be composted to more than 90%.    DETAILED DESCRIPTION - Device comprises an input hopper, crusher for crushing the organic waste and transferring into the input hopper, crushed material reservoir for storing the crushed material, returning unit which draws out and returns the stored crushed material to induce spraying of fermentation liquefied fertilizer including an aerobic microorganism, fermenting tank which mixes and stores the returned crushed material and seed compost and sprinkles the fermented liquefied fertilizer to firstly ferment it, agitating tank which agitates the firstly fermented mixture and sprinkles the fermented liquefied fertilizer to secondly ferment it, maturing tank which thirdly ferments and matures the secondly fermented mixture, compost reservoir which stores the matured compost, selection and package tank which returns 30% of the compost stored in the compost reservoir as the seed compost mixed with the crushed material and packs, selects, and ships rest, leachate reservoir which stores the leachate generated in the crushed material reservoir, sending unit, and fermenting tank, an aeration tank which gets returned the stored leachate and aerate the stored leachate, solid-liquid separation tank which separates solid and liquid from the aerated leachate, and treatment tank which adds the aerobic microorganism to the separated liquid to purify it and supplies it to the fermenting tank and agitating tank, where the crusher comprises first crusher which processes tough crush in a screw feeder form and second crusher which rotates in a high speed with one rotation unit of the wire and pulverizes again, returning unit is composed of first, second, and third conveyors, and magnetron which irradiates and dries microwave to maintain water content rate of the crushed material at 50-65%, crushed material is installed at the upper side of the first conveyor, magnetic separator which separates iron plates is installed at the upper side of the second conveyor, and fermented liquefied fertilizer sprinkler which sprinkles the fermented liquefied fertilizer for promoting fermentation and fermented mixture, fermented mixture is installed at the upper side of the third conveyor, seed compost conveyor which is installed horizontally at intervals with the third conveyor, third conveyor is equipped with fermentation tank and supplies the returned seed compost to the fermentation tank, and sawdust storage tank which is installed at the upper side of the seed compost conveyor to mix and supply sawdust to the returned crushed material and seed compost at a volume rate of 1:1:1. An INDEPENDENT CLAIM is included for method for composting the organic waste, which involves crushing the organic waste and transferring into the input hopper, mixing and storing returned crushed material and seed compost using fermenting tank, subjecting mixture to primary fermenter, transferring fermented mixture to secondary fermenter using agitation tank, maturing the fermented mixture, storing the matured compost using compost reservoir, storing leachate generated in the crushed material using leachate reservoir, sending unit, and fermenting tank, returning the stored leachate using an aeration tank, aerating the stored leachate, separating solid and liquid from the aerated leachate using solid-liquid separation tank, adding aerobic microorganism to the separated liquid for purification using treatment tank and supplying to the fermenting tank and agitating tank, mixing and supplying sawdust to the returned crushed material and seed compost at a volume rate of 1:1:1, irradiating and drying material using microwave to maintain water content rate of the crushed material at 50-65% and installing at the upper side of the first conveyor using magnetron, sprinkling the fermented liquefied fertilizer for promoting fermentation and fermented mixture installed at the upper side of the third conveyor using fermented liquefied fertilizer sprinkler, and returning 30% of the compost stored in the compost reservoir as the seed compost mixed with the crushed material using selection and package tank.