A charger circuit with temperature compensation function includes: a power converter, an input voltage sense circuit, an output adjustment circuit and a charging control circuit. The power converter converts an input voltage supplied from a photovoltaic power module to an output voltage. The input voltage sense circuit generates a signal related to the input voltage according to the input voltage. The output adjustment circuit generates an output adjustment signal according to the signal related to the input voltage. The charging control circuit generates a control signal according to the output adjustment signal, thereby adjusting a level of an output current supplied from the power converter. When a level of the input voltage is smaller than a predetermined voltage threshold, the power converter decreases the output current.