The invention discloses a free-form surface lens for double-quadrupole uniform illumination. A front surface flat surface and a rear surface free-form surface are connected with each other through a side cylindrical surface; the front surface flat surface is vertical to the propagation direction of laser beams; the rear surface free-form surface is used for deflecting the laser beams; a first free-form surface, a second free-form surface, a third free-form surface, a fourth free-form surface, a fifth free-form surface, a sixth free-form surface, a seventh free-form surface and an eighth free-form surface are connected with one another through a cylindrical surface; the laser beams are deflected by passing through the first free-form surface, the second free-form surface, the third free-form surface and the fourth free-form surface; an illumination area of the laser beams on a target surface corresponds to an inner ring in the double-quadrupole uniform illumination; the laser beams are deflected by passing through the fifth free-form surface, the sixth free-form surface, the seventh free-form surface and the eighth free-form surface; and the illumination area of the laser beams on the target surface corresponds to an outer ring in the double-quadrupole uniform illumination. The free-form surface lens has the advantages of simple and compact structure, good reshaping effect and high energy utilization rate.