Abstract: The corn straws and spent mushroom substrate were utilized as the conditioner for composting of kitchen garbage. The physical and chemical properties as well as maturity changes during the composting processes were investigated. The result demonstrated that spent mushroom was superior to the corn straws during aerobic composting of kitchen garbage. The system could increase to the desired temperature within three days, under a long stable high-temperature period up to nine days, the moisture and organic substrates decreased 19.6% and 20.2%, respectively. Meanwhile, the composting of kitchen garbage mixed with spent mushroom had the merit of less odor production and higher germination index of 55.6% after the first composting treatment.