This study aims to obtain a clean environment through agricultural activities by developing and evaluating the performance of a cyclone separating unit attached to threshers. Threshing in traditional method depends on emitting chopped wheat straw (Tibn) off the threshers freely in the air and then collected manually by operators causing air pollution and affecting operators' health. The developed cyclone in this study separates dust from the airstream and simultaneously collect the chopped wheat straw instead of operators. According to the obtained data from theoretical calculations (Table 1), the modifications on 2D2D cyclone. The tested performance parameters of the developed cyclone are: four airstream velocities (ASV) of 2.3, 3.6, 4.7 and 5.5 m/s; cyclone inlet dimensions (CID) of (A) 20x30; (B) 25x35; (C) 35x45 cm for width and height, respectively; vortex finder length (VFL) of 50, 60 and 70 cm; cyclone outlets ratios (COR) chopped wheat straw and airstream outlet diameters of 15, 20, 25 and 20, 25, 30 cm for chopped wheat straw and airstream outlet represents ratios of 0.75, 0.80 and 0.83, respectively. The results were summarized in the following points: Separation and collection efficiency value by developed cyclone was 99.8% at inlet velocity of 4.7m/s, vortex finder length of 50 cm, with inlet dimensions of 25x35 cm under cyclone outlet ratio of 0.8. The maximum values of the rising dust was 6.8 mg/m³under the same mentioned conditions while increased by97.5 % with traditional method (without cyclone). Total costs for packing chopped wheat straw under mentioned conditions decreased by 80% in case of using the developed cyclone comparing to the traditional method. It is recommended to manufacture the developed cyclone with vortex finder length of 50 cm, with inlet dimensions of 25x35 cm at outlet ratio of 0.8 to lessen the environmental pollution and conserve laborers' health.