A hybrid maximum power point tracking (MPPT) with adaptive step-size based on single sensor for photovoltaic systems is proposed. The MPPT method combines with the fractional open circuit voltage method (FOCV) and adaptive step-size method can achieve quick and accurate tracking. From the simulation results, the characteristics of PV voltage have trend that can converge at the maximum power point (MPP). However, a system with single sensor will have large oscillations. The MPPT adopted adaptive step-size can effectively product a stable output power. The experimental structure is mainly constructed with boost converter, and the simulation results have been proposed to verify the system performance.