Radio Frequency Identification (RFID) technology has become widespread in the supply chain. RFID uses signals transmitted from tags attached to items to track and identify the items. The contents of the items cause weak signal strength and low tag read rate. However, this feature helps to detect whether or not there is a hollow in a pallet. Hollows in pallets are usually caused by the theft of items. This thesis details research that aims to detect the hollow based on a pallet filled with a high water content product. The result suggests that the hollow pallet can be detected by observing the difference in the number of detected tags between the full pallet and empty pallet. Furthermore, by analyzing the data from individual tags, the position of the hollow in the pallet can be determined.