An apparatus for determining the particle size distribution and for characterizing the particle shapes of a particle mixture has a metering device for classifying a particle mixture supplied in a particle stream to the apparatus. An optoelectronic measurement section is provided that has a light source and an image collecting device aligned with one another, wherein the particle stream is guided between the light source and the image collecting device. The image collecting device has a plurality of electrooptical image recording units directed onto the particle stream and having different image recording scales matched to one another to cover the whole measurement range of the apparatus. A computing unit converts digital image points recorded by the recording units into a size determination of the particles.