A refrigeration device having a refrigerant circuit , the refrigeration device comprising: a high-voltage electrical parts group including cooled elements (103, 142a to 142c, 143a to 143c, 106) that require cooling; a low-voltage electrical parts group; a printed wiring board ; and a refrigerant jacket configured to cool the cooled elements by refrigerant flowing through the refrigerant circuit, wherein the high-voltage electrical parts group and the low-voltage electrical parts group are mounted on one main surface of the printed wiring board, characterized in that : the high-voltage electrical parts group includes a plurality of reactors (141a to 141c); the high-voltage electrical parts group configures an interleaved power supply circuit ; the cooled elements configuring the power supply circuit are placed in an order conforming to a power supply path of the power supply circuit; the power supply circuit has a rectifier circuit , a power factor improvement circuit , smoothing capacitors (105a to 105c), and an inverter circuit ; the power factor improvement circuit has the plurality of reactors connected to each other in parallel and diodes (142a to 142c) and switching elements (143a to 143c) serving as the cooled elements connected to each of the reactors; and the reactors are placed on the opposite side of the smoothing capacitors, with the diodes and the switching elements configuring the power factor improvement circuit being sandwiched in between. a high-voltage electrical parts group including cooled elements (103, 142a to 142c, 143a to 143c, 106) that require cooling; a low-voltage electrical parts group; a printed wiring board ; and a refrigerant jacket configured to cool the cooled elements by refrigerant flowing through the refrigerant circuit, wherein the high-voltage electrical parts group and the low-voltage electrical parts group are mounted on one main surface of the printed wiring board, characterized in that : the high-voltage electrical parts group includes a plurality of reactors (141a to 141c); the high-voltage electrical parts group configures an interleaved power supply circuit ; the cooled elements configuring the power supply circuit are placed in an order conforming to a power supply path of the power supply circuit; the power supply circuit has a rectifier circuit , a power factor improvement circuit , smoothing capacitors (105a to 105c), and an inverter circuit ; the power factor improvement circuit has the plurality of reactors connected to each other in parallel and diodes (142a to 142c) and switching elements (143a to 143c) serving as the cooled elements connected to each of the reactors; and the reactors are placed on the opposite side of the smoothing capacitors, with the diodes and the switching elements configuring the power factor improvement circuit being sandwiched in between. the high-voltage electrical parts group includes a plurality of reactors (141a to 141c); the high-voltage electrical parts group configures an interleaved power supply circuit ; the cooled elements configuring the power supply circuit are placed in an order conforming to a power supply path of the power supply circuit; the power supply circuit has a rectifier circuit , a power factor improvement circuit , smoothing capacitors (105a to 105c), and an inverter circuit ; the power factor improvement circuit has the plurality of reactors connected to each other in parallel and diodes (142a to 142c) and switching elements (143a to 143c) serving as the cooled elements connected to each of the reactors; and the reactors are placed on the opposite side of the smoothing capacitors, with the diodes and the switching elements configuring the power factor improvement circuit being sandwiched in between. <EOS>