NOVELTY - Aerobic composting method of organic solid waste by thermal hydrolysis at high temperature, involves (a) preheating organic solid waste, (b) performing thermal hydrolysis of preheated organic solid waste, (c) cooling hydrolyzed organic solid waste, (d) dewatering the organic solid waste, subjecting the organic solid waste to anaerobic effluent treatment, mixing obtained filter cake with conditioning agent, and processing and uniformly crushing the mixture, and (e) performing aerobic composting process, and reusing a portion of product for backmixing process.    USE - The method is useful for aerobic composting of organic solid waste chosen from sewage sludge including sewage sludge of factory, papermaking sludge, organic waste, kitchen waste, livestock manure, and feces in septic tank by thermal hydrolysis at high temperature (claimed).    ADVANTAGE - The method reduces usage amount of conditioning agent, consumes less time for composting process, and improves compost processing capacity by 2-3 times.    DETAILED DESCRIPTION - Aerobic composting method of organic solid waste by thermal hydrolysis at high temperature, involves (a) preheating 10-15% organic solid waste at 80-95 degrees C using heat exchanger, (b) adding preheated organic solid waste to hydrolysis tank, and performing thermal hydrolysis at 0.4-1 MPa and 150-190 degrees C for 15-90 minutes, (c) cooling hydrolyzed organic solid waste to 70-85 degrees C, and conveying cooled organic solid waste to intermediate storage pool, (d) adding the organic solid waste to plate and frame filter press for dewatering the organic solid waste such that the water content of the organic solid waste is 35-50%, performing anaerobic treatment to produce biogas, adding biogas to boiler to produce steam, subjecting the organic solid waste to anaerobic effluent treatment, adding obtained filter cake to multi-shaft stirrer, then adding conditioning agent to the stirrer, uniformly mixing the components in the stirrer, processing obtained mixture, and uniformly crushing the mixture using crusher, and (e) adding product obtained in step (d) to aerobic composting system for performing aerobic composting process at high temperature, reusing a portion of product for backmixing process, and obtaining other portion of the product as organic nutritional soil.