When photovoltaic (PV) array is operated under partially shaded condition (PSC), power-voltage curve will show multiply peaks. This causes the inability of conventional maximum power point tracking (MPPT) methods such as hill climbing (HC). To deal with this problem, this paper proposes a new MPPT method based on a modified cat swarm optimization (MCSO) to achieve global maximum power point (GMPP) tracking. To assess the performance of proposed method, different simulations and experiments have been carried out. The proposed method can successfully track GMPP under different PSCs. Furthermore, MCSO based MPPT method shows a high tracking accuracy and convergence speed as compared with other MPPT methods. (C) 2017 Elsevier Ltd. All rights reserved.