Photovoltaic power generation system has key rule in electricity production. Although, it is clean renewable energy with unlimited resources but it has some drawbacks in efficiency. In order to maximize the efficiency, PV array must drive at maximum power point. For the reason so, several algorithms are used in PV system to track MPP and reduce the operational losses. The pert and observe P&O algorithm is most commonly used because of its simplicity and low cost. Though it is easy to install, but it has ripple drawback when it reaches to MPP. In this paper improved pert and observe P&O MPPT control technique is introduced by the addition of PI controller to the algorithm. In this method ripple around maximum power point are removed under stable external environment and unstable condition. At the end simulation is performed. Simulation results shows that the improved method MPP tacking effect is improved and the efficiency is also slightly increased.