Aiming at the shortcomings of the existing radio sonde, such as high power consumption, high communication cost and low data accuracy, a high-altitude data acquisition system based on WSN technology is designed. In the circuit design, the system takes STM32 chip as the control core, selects low-power sensor module to realize environmental data acquisition and geographical location monitoring, transmits it to the upper monitoring layer through LoRa technology, and the upper computer administrator carries out on-line monitoring of high-altitude meteorological data. In the software design, the TDMA slot allocation protocol is improved to improve the reliability of data transmission, and the dynamic weighted average fusion algorithm is applied to the data fusion experiment. The connectivity, reliability and operability of the system are verified by experiments, which plays a positive role in improving the domestic space meteorological data acquisition business.