5%左右。The online monitoring of grain loss was important for improving the effect of harvest. Based on the requirement of measurement, the polyvinyliden fluoride(PVDF) piezoelectric-film was applied to develop a novel grain loss sensor array. The design of conditioning circuit was also discussed. The spatial distribution of grain loss could be easily obtained by proposed sensor array. Three kinds of full rice seeds with different moisture were prepared for the experiment, and the results indicated the measuring error of the sensor were within 5%.