Abstract: In order to meet needs of management and development of precision agriculture，a single plate impact grain yield sensor for real-time yield detection was designed.In order to verify feasibility of the method，finite element simulation of the sensor was carried out，the stress cloud diagram of stress plate was formed，and detection position of strain gauge was determined.Wheatstone bridge was used to collect deformation signal of the stress acquisition board and send it to upper computer through CAN.After deformation signal was processed by unscented Kalman filter（UKF）algorithm，the real-time production information was obtained by calibrating relation curve.Stress calibration test determined relationship curve between analog value collected by sensor and impact；yield calibration test determined relationship curve model between impact and yield；field test showed that average absolute error of the sensor was 4.6%.