The invention relates to a garbage classification system and process. The garbage classification system involves conveyors, a magnetic separator and a stock bin, wherein the magnetic separator is arranged above the first conveyor, the stock bin is arranged at one end of the second conveyor, a bag breaking motor and a bag breaking roller are arranged below the stock bin, the third conveyor is arranged below the stock bin, the third conveyor conveys garbage to a crushing and screening machine, a screening plate is arranged in the crushing and screening machine, the plurality of fourth conveyorsare arranged below the screening plate, and one end of the crushing and screening machine is used for conveying the garbage to an air separator through the fifth conveyor. According to the garbage classification system and process, the garbage can be subjected to classification treatment, the garbage with a large volume can be crushed in the classification process, and the mixed garbage is screened, so that the garbage, with light weight and generated in the sorting and classifying process, is easy to collect, then treatment or recycle is facilitated, the structure is simple, and the manufacturing cost is low.