Power supply for simulating solar cell and method thereof

A power supply for simulating solar cell and method thereof are provided in the present invention. In the power supply, an output module is provided to generate a plurality of power-supply-output voltages which are respect to a plurality of measurement procedures. A measurement module is provided to measure a plurality of output voltage values which are respect to the power-supply-output voltages in the measurement procedures. A simulation module is set at least one solar cell parameter which includes an open-circuit voltage value, a short-circuit current value, and a resistor value. The simulation module is provided to simulate a plurality of solar cell simulation current values for every output voltage values according to a difference of short-circuit current value and the voltage values is equal to a product of the resistor value and the solar cell simulation current value to simulate a voltage-current curve of the solar sell.