Design and simulation analysis of braking system for ATV is carried out with the assistance of Ansys and MATLAB. Heat generated increases the temperature of the disc brake at the rubbing surface resulting in thermal stresses in the components of the braking system. Static, structural, thermal, computational flow dynamics, vibrational & fatigue behavior of ventilated brake disc rotor, hub and upright are analyzed. Stainless Steel, SS-410 material configuration has been considered for disc brake rotor and results obtained are analyzed in terms of performance, longevity and efficiency. Braking efficiency and stopping distance curve are analyzed from their characteristics plot. Vibrational behavior, structural behavior, thermal behavior, performance efficiency, flow behavior of ventilated disc brake rotor can be easily depicted with respect to bump and droop during acceleration, high climb and maneuverability. Ventilated disc brake Rotor with outer diameter of 220 mm is used. Comparison of obtained results from designed ventilated disc brake rotor with results of available designed disc brake rotor has been carried out. Al-7075 material configuration has been considered for hub & upright and results obtained are analyzed in terms of performance, longevity and efficiency. Rectangular base design of hub has helped to increase the overall strength by adding material to the stress concentrated area. Force calculation has been carried out for designing disc brake rotor, hub and upright. Structural behavior plots are depicting the deformation behavior at each node. Thermal behavior plots are depicting the temperature contours over the temperature range. Vibrational frequency at different modes are depicting the nature of vibration occurring on the brake rotor disk and computational Flow dynamics analysis is depicting the flow behavior of the Disk brake Rotor. Very fine meshing has been carried out for analysis in order to obtain more efficiency.