The utility model discloses a low-power-consumption wireless sensor network system and a controlling and awaking method thereof. A network coordinator module in the low-power-consumption wireless sensor network system sends a low-frequency awaking signal to a slave node module and awakes a target node as required through the low-frequency awaking signal when the target node needs to be awaked, the target node is utilized more effectively, so that the effective utilization rate of the node power is greatly improved, the service life of the wireless sensor network system is prolonged to a certain degree, the performance of the wireless sensor network system is improved, and energy-saving and environment-friendly ideas are embodied.