There is provided a sensor node management method in which a user is unconscious of a service break even when a sensor mode has failed among a plurality of sensor nodes assuming intermittent operation. Moreover, it is possible to provide a flexible sensor node management method capable of freely modifying the observation grading (space, time) in accordance with a user's desire. A base station (30) for containing a plurality of intermittently operating sensor modes includes a sensor management table (4) for managing the sensor nodes, a group management table (5) for grouping a plurality of sensor nodes, and an operation timing control unit (3). The operation timing control unit (3) decides the operation interval and the relationship for starting each of the sensor nodes. Moreover, the base station and the sensor node have a counter value as a reference of the sensor node operation interval and the operation start phase, which are periodically synchronized.