Multi-layer shuttle car racks use material boxes as storage units, which are divided into single-deep position and double-deep position. Each layer is provided with a track. Through the shuttle car running on the track, the goods in and out of the box are realized. This kind of shelf space has a high utilization rate, and cooperates with shuttle vehicles, conveyor lines, elevators and other equipment to form a high-density storage system, which can realize the 'goods to people picking' working mode.