5%。A dual-plate differential impact-based yield sensor was designed to eliminate the influences of the vibration signal. Two similar parallel plates were mounted in front of the outlet of the combine harvester. The front plate was used to detect the impact of grain out of elevator the harvester as well the vibration. The rear plate was used to detect the vibration only. A differential circuit was used to eliminate the vibration signal of the harvester. The experimental waves showed that the vibration signals of the two plates were similar while the harvester runs with no grain input. The influence of the vibration could be eliminated by the differential circuit. The zero drift of this sensor is less than 0.01g/s. The error of the yield sensor is less then 3% at flow rates 0.5～2kg/s in lab. It is not greater than 5% in field condition.