Abstract: This invention discloses a switching power converter controlled by a winding voltage sampler, including an input circuit with an input end, an output circuit with an output end, one or more switches, a controller to regulate on/off of the switch, a winding voltage sampler, and a transformer including a primary-side coil assembly connecting the switch and the winding voltage sampler, and a secondary-side coil assembly. The output circuit connects the secondary-side coil assembly; the winding voltage sampler detects preset reference voltage of the primary-side coil assembly for the controller to regulate output voltage.