An all-terrain wheelchair is a lever propelled wheelchair which enables an individual to drive on all terrains easily as the driving mechanism is efficient, ergonomic and fast. It also increases the reach capabilities and social boundaries of disabled. The paper is divided into two parts. In the first part, a comparative study of push rim wheelchair and All-terrain Wheelchair (lever propelled) has been done. In the second part, Optimization of this All-terrain Wheelchair has been done.The comparison is done on various parameters such as peak velocity, average velocity, acceleration, retardation, stroke frequency, reduction in effort, mechanical efficiency, obstacle climbing ability, turning radius, the distance travelled per stroke, Pressure cuts and burns caused during propelling the chair. Biomechanical testing is also done considering the heart rate and oxygen consumption level. This information was used to determine the energy demand, which is intrinsically connected to a wheelchair's mechanical efficiency.The optimization mainly focuses on ergonomics and efficiency of design. For this, the main emphasis was given on factors like the position of lever-drive system, configuration of wheel, seating, backrest, chassis, breaking and foot rest. this optimized design would make the chair more efficient and easy to use by enabling the person to drive, steer, and stop without even touching the wheels, thus, eliminating the risk of friction burns and protecting the wrists and shoulders from repetitive stresses.The analysis was done using commercial software ANSYS and CATIA and validation of results was conducted with the users and non-users of wheel chair.