The invention discloses a wedge-shaped part press-riveting device and method. An upper pressure head assembly and a lower pressure head assembly of the press-riveting device are mounted on an arch-shaped frame from top to bottom; the upper pressure head assembly comprises an angle self-adaptive upper pressure head mechanism and a pressing cylinder; the pressing cylinder is vertically and fixedly arranged on the arch-shaped frame; the angle self-adaptive pressure head mechanism is arranged at the bottom end of a piston rod of the pressing cylinder; the lower pressure head assembly comprises an angle self-adaptive lower pressure head mechanism and a lower pressure head height adjusting mechanism; the lower pressure head height adjusting mechanism is arranged on the arch-shaped frame; and the angle self-adaptive lower pressure head mechanism is arranged at the top end of the lower pressure head height adjusting mechanism. The wedge-shaped part press-riveting method comprises the following steps of: loosening an upper pressure head positioning bolt and a lower pressure head positioning bolt; starting the pressing cylinder, and enabling the piston rod to descend to the maximal stroke position; putting a wedge-shaped part, enabling the lower pressure head to rotate in a self-adaptive mode, and enabling the upper surface of the lower pressure head to be in tight fit with the lower surface of the wedge-shaped part; lifting the lower pressure head, and enabling the upper surface of the wedge-shaped part to be in tight fit with the lower surface of the upper pressure head; screwing up the upper pressure head positioning bolt and the lower pressure head positioning bolt; returning the piston rod of the pressing cylinder to the initial position; mounting rivets; and starting the pressing cylinder to apply pressure to the rivets, thereby completing riveting.