A switching power supply device includes first to fourth switches sequentially connected in series, an inductor, a first capacitor whose first end is connected to a connection node of the first switch and the second switch and whose second end is connected to a connection node of the third switch, the fourth switch, and the inductor, a second capacitor whose first end is connected to a connection node of the second switch and the third switch, and a controller that controls switching on and off of the first to fourth switches. In at least one of a first pair configured with the first switch and the third switch and a second pair configured with the second switch and the fourth switch, the controller shifts a timing of switching from off to on between two switches.