Alfalfa is the queen of forage plants. Leaves contain two-thirds of the Protein and 75 percent of the total digestible nutrients (TDN) in alfalfa hay. Harvesting the maximum amount of the leaves is a profitable way to produce alfalfa. Little consideration is given to the losses in yield and quality that can occur during the harvesting operation. In addition, most forage losses are the most nutritious (highly digestible or protein) component of the plant. Because of this, nearly all losses not only reduce the amount available for animal consumption, but also reduce the quality of the feed. It is the combination of reduced quantity and reduced quality which contributes to the economic loss. Therefore to overcome this problem, it is necessary to design, fabricate and evaluate a device for gathering the leaves without damage them. In this research a leaves gathering was designed and fabricated. A pneumatic system is the ideal conveying and separating system for this aim so in this research a pneumatic collector was designed to gather leaves left on the ground as a result of shattering leaves during bailing operation. To separate additional materials such as gravel and dust a cyclone was designed which its basic cylinder and cone height dimension was calculated based on aerodynamic properties of the leaves and JCS standard. Cyclones provide an efficient and costeffective means of separating particulates (material) from air. Cyclones operate by generating a vortex of particulate laden air. Centrifugal force pushes the particulates toward the outer cyclone wall where they lose velocity and spiral downward to the discharge. Knowledge of the aerodynamic properties of leaves like its terminal velocity is needed in equipment design pneumatic conveying. Wolf and Tatepo, method was used for the terminal velocity measurement. The terminal velocity was determined by measuring the air velocity required to suspend a particle in a vertical air stream using a wind tunnel. The mean value of terminal velocity was 4.029 m/s. The machine was connected to tractor by means of a single hitch point. System was evaluated in forward velocity of tractor (2, 4 and 6 km/h) with four replications. Complete block design was used to conduct experiments. According to the result of evaluating system, quality decrease as forward velocity increase and at the lower forward velocity, system can show the best operation in gathering leaves. It can show the best operation in separating leaves f