The effect of the reflectivity of the output mirror on the single-mode multi-quantum wells (MQWs) vertical cavity surface emitting lasers (VCSEL) performances is investigated. Relevant VCSEL design with numerous (DBR) pairs has been designed and characterized using laser technology-integrated simulation program ISETCAD. The number of quarter-wave DBR that remaining in the upper mirror could be used to achieve the optimum performance of VCSEL in a top surface emitting geometry, such as maximum output power, threshold current, slope output efficiency, differential quantum efficiency and mode gain.