Manufacturing method of rigid-flex circuit board

A manufacturing method of a rigid-flex circuit board comprises the following steps: providing a double-sided copper-clad plate comprising a first copper foil, a first insulating layer and a second copper foil; circuit manufacturing is conducted on the double-face copper-clad plate, the first copper foil correspondingly forms two supporting pads, the second copper foil correspondingly forms a first circuit layer, and therefore a middle structure is obtained, and the first circuit layer is provided with first openings corresponding to the supporting pads; providing a second insulating layer, and forming a second opening of which the width is greater than the distance between the opposite surfaces of the two supporting pads; the middle structure, the second insulating layer and a flexible circuit substrate are laminated, and each supporting pad at least partially corresponds to the corresponding second opening; an outer layer circuit structure is formed on the side, away from the second insulating layer, of the