The invention relates to the technical field of sensors, particularly a wireless sensor. The wireless sensor comprises a data acquisition module, a data processing module, a radio-frequency module and a power supply module which are sequentially superposed from bottom to top, wherein the data processing module is respectively connected with the data acquisition module and radio-frequency module, and used for receiving data acquired by the data acquisition module and storing the data, and meanwhile, transmitting the data to a wireless base station through the radio-frequency module; and the power supply module is respectively connected with the data acquisition module, data processing module and radio-frequency module and used for supplying power. The data acquisition module, data processing module, radio-frequency module and power supply module are installed on the bottom plate of the sensor from bottom to top, and such installation mode can greatly reduce the volume of the sensor. The wireless sensor does not need any cable, has the characteristics of small size, light weight, low power consumption, high storage capacity, long working time and the like, and has wide application prospects and favorable economic benefits.