A stock management method and system utilizes a mat that includes a plurality of sensors corresponding to a plurality of sensing areas, each of sensors is configured to sense an item placed on a certain sensing area. Partitions define a plurality of lanes on the mat. A controller receives sensing results of the plurality of the sensors and calculates a stock level of remained items on the mat based on the sensing results. One of the sensing areas is located in both of two lanes of the plurality of lanes.