PROBLEM TO BE SOLVED: To provide a behavior monitoring device which supports in the determination of a monitored person who has to be addressed with priority even when a plurality of monitored persons sit up at the same time.SOLUTION: A behavior monitoring device 10 comprises: a storage unit 13 that stores a required time from when a monitored person sits up on a bed 3 to when the person assumes an edge-sitting posture in which the monitored person sits at an edge of the bed with his/her feet on a floor or a standing posture in which the monitored person stands on the floor; a communication unit 14 that communicates with terminal devices 20a and 20b; a detection unit 11 that detects a sitting up of the monitored person on the bed 3; and a control unit 12 that, when the sitting up of the monitored person is detected by the detection unit 11, notifies the terminal devices 20a and 20b of a fact that the sitting up of the monitored person has been detected, and of the required time stored in the storage unit 13 via the communication unit 14.SELECTED DRAWING: Figure 1COPYRIGHT: (C)2020,JPO&INPIT【課題】複数の被監視者が同時に起き上がった場合であっても優先的に対応すべき被監視者を決定することを支援する行動監視装置等を提供する。【解決手段】行動監視装置10は、被監視者がベッド3上で起き上がってからベッド3の端部に腰掛けて床に足をついた状態である端座位又は床に立った状態である立位になるまでの所要時間を記憶している記憶部13と、端末装置20a及び20bと通信する通信部14と、ベッド3上での被監視者の起き上がりを検知する検知部11と、検知部11によって被監視者の起き上がりが検知されたときに、被監視者の起き上がりが検知されたこと、及び、記憶部13に記憶されている所要時間を、通信部14を介して、端末装置20a及び20bに通知する制御部12とを備える。【選択図】図1