Micro Air Vehicle (MAV) is the current research and development work worldwide. This work describes the design and optimization method of Micro Air Vehicles. Here the optimization method to minimize the vehicle size, the objective function for this optimization problem, for the set of design variables is found from the aerodynamic analysis. This aerodynamic analysis is mainly based on the results obtained from the wind tunnel. Optimization for improving the endurance is explained in the similar way as the optimization problem of minimizing the size of the vehicle with the slight change in the objective function.