The invention provides a method for filtering an official seal of an invoice. The method comprises the following steps of receiving an invoice picture in which filtering of the official seal is required, and converting the invoice picture to a pixel matrix; obtaining a pixel point set from the pixel matrix, and classifying all pixels in the pixel point set; performing picture restoring on all pixels in each class after classifying according to the coordinate in the invoice picture, and obtaining a plurality of layers, wherein the number of the layers is same with that of the classes; identifying each layer by means of an OCR open-source engine; calculating an identification score of each layer, and utilizing the layer with a maximal identification score as the picture in which the official seal is filtered. The invention further relates to a device for realizing filtering the official seal of the invoice. The method and the device for filtering the official seal of the invoice has beneficial effects of improving an identification rate, increasing an identification speed, realizing relatively convenient system maintenance and reducing cost.