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Currently, the automation level of sand samplers used for farmland soil wind erosion is very low. In addition, they can’t record the sediment data real-timely and have no functions of wireless transmission and networking. So it brings many difficulties and other issues to the study on motion characteristics of the soil wind erosion particles at different stages in the transport process. To solve these problems, a new type of automatic multi-channel wireless sand sampler based on wireless sensor network technology and the reverse hedge sand separator was designed. It was dedicated to study agricultural soil wind erosion and realize these functions of automatic acquisition of quantity of soil wind erosion, wireless transmission and real-time data processing. The results showed that the system can circularly scan up to six testing points, the eight channels of each testing point and automatically collect wind erosion data, and the maximum response time was no more than 2s. The rotating start-up wind speed of the sand sampler was 3.4m/s, and the maximum weighing range was 0~180g; the precision of weighing sensors was up to 0.01g and 10 hours continuous measurement error was within ±0.04g with sampling efficiency more than 85%. The length of data packet was 32 bytes and the effective transmission distance can reach 1000m under the conditions of 1kb/s transfer rate and maximum transmitting power. Communication setup time was less than 5s. The system had advantages of low power consumption, easy to use, simple operation and automatic data acquisition, it can meet the needs of research on farmland soil wind erosion.