[Objective] This study aims at discussing the harmlessness treatment and maturity safety of waste vegetable leaves with microbial agent, in order to solve the problems of environmental pollution during fermentation, and improve the porosity, ventilation and temperature of fermentation reactor.[Methods] Waste vegetable leaves were used as raw materials, corn straw and cow dung were used as auxiliary materials, and methods such as adjusting the carbon-nitrogen ratio of fermentation raw materials, types of microbial inoculum, moisture and temperature of fermentation stack were adopted.[Results] The optimal ratio of microbial fermentation raw materials for waste vegetable leaves was optimized, and the weight ratio of waste vegetable leaves, corn stalks, cow dung and fermenting agent was 100:4:2:0.25. A set of evaluation system for microbial fermentation maturity index of waste vegetable leaves was established. The temperature of the fermentation reactor was ≥ 50℃, lasts for 3~5 days, pH value was ≤ 8.0, conductivity was ≥ 2.0 mS/cm, E₄/E₆ ratio was ≤ 2.5, C/N ratio was < 20, and germination index GI was >80. The nutrients and safety limit indexes of total nitrogen, organic matter, alkali nitrogen and available potassium of the fermentation products were in line with industry standards.[Conclusion] The pH value, electrical conductivity, E₄/E₆, C/N, GI and other physicochemical and biological indicators of the product of microbial fermentation in the waste cabbage leaves all meet the requirements of the fertility and safety limits of vegetable cultivation matrix.