Abstract: The invention relates to the method for milling and separation into fractions of solids and granular materials in a controlled airflow. The device for milling and separation of solids and granular materials consists of a round milling chamber with a system of pneumatic separation comprising of a vertical cylindrical body that has an uploading slot for solids and granular materials and unloading channels for the milled products of light, medium and coarse fractions. A rotating disc and a conical divider are located inside a vertical cylindrical body. The rotating disc has plates (hammers) and removable blades of different sizes and configurations. System of pneumatic separation consists of a milling chamber, an air slugcatcher, channels for the milled material, and a chamber of higher pressure. Such construction of the device allows to obtain products of a highest quality, and to improve the separation by dividing the material into three fractions: light, medium and coarse.