Of late there has been an increase in use of wireless communication system. The recent approach used is Massive-MIMO technology. But in the current scenario where spectrum is limited, the demand for high data degrades the quality of services. Therefore, OFDM system was proposed. Though coupling OFDM system with MIMO can further improve the performance of next generation wireless systems, there are certain issues like antenna design, channel estimation, PAPR etc. which requires due consideration. Amongst them, PAPR is the major problem that contributes high in performance degradation. To overcome this issue, Modified Firefly algorithm is used which was inspired the behaviour of fireflies. With the firefly algorithm, PAPR is highly reduced leading to better performance.