The WSN has various problems to be resolved in order to spread its usage widely. One of the problems is the power consumption of the sensor node driven by the battery. Changing the batteries on many nodes incurs significant cost. To tackle such problem, the sensor nodes using photovoltaics have been proposed [2]. However, the photovoltaics cannot generate enough power in nighttime. It also does not work well when enough sunlight cannot reach like the indoor, cloudy day, tunnel, and so on. There are also several researches using other energy harvesting such as vibrations, thermoelectric, wind flow, acoustic noise, magnetic field energy, and so on. However, the amount of energy gained by such harvesting is not enough to make the sensor node work normally and reliably [2]. By the way, there are researches to make the battery life longer by making the sensor node sleep with low power consumption in a cyclic manner [3]. However, the sensor node in the sleep mode constantly consumes the battery power even if it is low. In addition, the cyclic wake-up performs waste sensing when any event does not occur. It leads to waste of the battery power.Thus, we propose a novel architecture of the sensor node with zero power consumption in the sleep mode. Since the sleeping sensor node also wakes only when the event that the sensor should sense occurs, the waste wake-up consuming the battery power can be eliminated completely. The proposed sensor node utilizes a transistor switch cutting the power line, which is driven by the electromotive force from a sensor [4]. The novelties of our paper are to propose the new architecture of the sensor node using this mechanism on a sensor network, to confirm whether a wireless sensor node with this mechanism can be practically realized, and to show the quantitative effect to reduce the power consumption.The rest of the paper is organized as follows. Section 2 shows an overview of the architecture of the proposed Abstract The wireless sensor network (WSN) is a promising technology to improve the social life cooperating with the robotic technologies like nursing robots, disaster rescue robots, industrial robots, and so on. For such WSN, we propose an architecture of the sensor node with zero standby power consumption. This is accomplished by combining a power transistor cutting the ground line, an electromotive from a sensor for just turning on the power transistor and a conventional battery. The preliminary experiments demonstrate that our proposal can actually activate the sensor node, which stays at the sleep mode with zero power consumption, with a short-time electromotive force generated by the piezoelectric sensor. It is also confirmed that the sensor node activated can establish the wireless communication correctly.