The invention relates to a method for producing 2,3-butanediol by utilizing carbohydrate garbage. The method comprises the following steps: S1, acquiring sludge containing soluble protein SPN, and carrying out digestion pretreatment on the sludge by using microwaves under the treatment conditions that the temperature is raised to 100 DEG C in 15 minutes, and then the temperature is kept for 0-20 minutes; and S2, mixing the carbohydrate garbage and the pretreated sludge according to different mass ratios, putting the obtained mixture into a reaction container, adding water to enable the mass concentration of a substrate to be 2%-5%, performing a stirring reaction under the condition of the constant temperature of 35 DEG C, and adjusting pH values of reactants in the reaction container to 6every other 12 hours. According to the invention, the sludge is added to promote the carbohydrate garbage to produce 2,3-butanediol, so that the problem of organic solid waste in the environment is solved, and resource utilization is carried out.