PROBLEM TO BE SOLVED: To provide a system for easily detecting a getting-on behavior.SOLUTION: A getting-on behavior detection system is configured so that: a getting-on side device 10 which is attached to a forehead of a cattle which gets on, which transmits a transmission signal, and has a rechargeable battery 15 and a device 20 which is a side to be got on, which is attached on a position of a range of a back to a tail of a cattle which is a side to be got on. When a cattle gets on other cattle, an ID of the cattle which gets on other cattle is transmitted from the device 20 which is a side to be got on, according to the transmission signal. A combination of the cattle which is got on, and a cattle unique ID of the getting-on side device of the cattle which gets on, is detected. The getting-on behavior detection system comprises a battery charger for sending power in a non-contact manner to the rechargeable battery 15.SELECTED DRAWING: Figure 2COPYRIGHT: (C)2017,JPO&INPIT【課題】乗駕行動を容易に検知するシステムの提供。【解決手段】乗駕する側の牛の顎に取り付けられ、発信信号を発するとともに、充電池15を有する乗駕側装置10と、乗駕される側の牛の背中から尾までのいずれかの位置に被乗駕側装置20を取り付け、乗駕した時に、前記発信信号に応じて乗駕した牛のIDを応答信号として被乗駕側装置20から送信し、乗駕した牛の乗駕側装置の牛固有IDと合わせて乗駕された牛の組み合わせを検出するシステムで、充電池15に対して、非接触にて電力を送信する充電装置を含む乗駕行為検出システム。【選択図】図2