The present disclosure provides a power supply device and a high-power illumination system. The power supply device includes: a housing, where the housing includes a first bottom plate having a first surface on which a first heat sink is provided and a second surface on which a thermal conductive potting layer is provided; and a printed circuit board, where the printed circuit board is located in the housing, the printed circuit board includes a circuit board body and multiple electronic components arranged on the circuit board body, at least part of the multiple electronic components is arranged facing the second surface of the first bottom plate, and the electronic component of the at least part of the multiple electronic components is partially immersed in the thermal conductive potting layer to conduct heat dissipated by the electronic component to the first heat sink for natural heat dissipation of the electronic component.