Abstract: The subject of the invention is a method and a device for measuring of solid matter particles of pulp suspension, in which method a sample of pulp suspension is separated and scanned and the amount and the quality of solids are examined from the picture. According to the method the sample separated from a pulp suspension with know consistency of dry substances is fed at known feeding speed onto the wire, which is an endless loop and moves at know speed, and where water is removed with a drying device from the sample, and which transports the sample mainly as a constant matt to a camera device, where the sample is scanned and on the basis of this picture and information about the feeding speed of the sample, moving speed of the wire and the consistency information the absolute and/or relative amount and quality of solids are measured.