In a central processing device and a central processing method for use in a subject observation system and a subject observation system according to the present invention, a care name indicating a name of a care service, a care timing indicating a timing of performing the care service and a sensor identifier possessed by the sensor unit corresponding to a subject as a target who receives the care service are stored while being associated with each other, and the care name associated with the care timing is notified together with an image acquired from the sensor unit having the sensor identifier associated with the care timing to a predetermined terminal device in accordance with the care timing.
