Production of aerosol by dry dispersion is important for many technical processes, e.g., coating. The desagglomeration of materials from the product class nanoparticle flocks is a specific challenge. An insight in results and experiences by the dry desagglomeration with an air classifier mill (jet mill) is given. The variable main influences are the cage wheel ratio, the process air flow, the specific surface of the model substances and the length of the transport pipe.