A hybrid resistance adjustment system used on an exercise bike which has a frame and a flywheel mounted on the frame, and the hybrid resistance adjustment system comprising a resistance assembly (10A, 10B) mounted on the frame and having a mounting seat (11A, 11B) pivotally connected to the frame; a brake pad mounted on the mounting seat (11A, 11B); and at least one magnetic set mounted on the mounting seat (11A, 11B) and each of the at least one magnetic set having two magnetic elements respectively located on opposite sides of the flywheel; a manual adjustment assembly mounted on the frame; and an electronic adjustment assembly (30A, 30B) mounted on the frame and having a linearly movable component moving linearly relative to the frame; and a motor connected to the linearly movable component and selectively driving the linearly movable component to move linearly and push the mounting seat (11A, 11B) of the resistance assembly (10A, 10B) to simultaneously make the brake pad abut against the flywheel and make the at least one magnetic set approach the flywheel; and the resistance assembly (10A, 10B) further has a restoring spring mounted on the frame and connected to the mounting seat (11A, 11B), the restoring spring being capable of driving the mounting seat (11A, 11B) to return to an original position; the hybrid resistance adjustment system characterized in that: the manual adjustment assembly has a shaft being linearly movable relative to the frame and selectively pushing the mounting seat (11A, 11B) of the resistance assembly (10A, 10B) directly to simultaneously make the brake pad abut against the flywheel and make the at least one magnetic set approach the flywheel. a resistance assembly (10A, 10B) mounted on the frame and having a mounting seat (11A, 11B) pivotally connected to the frame; a brake pad mounted on the mounting seat (11A, 11B); and at least one magnetic set mounted on the mounting seat (11A, 11B) and each of the at least one magnetic set having two magnetic elements respectively located on opposite sides of the flywheel; a mounting seat (11A, 11B) pivotally connected to the frame; a brake pad mounted on the mounting seat (11A, 11B); and at least one magnetic set mounted on the mounting seat (11A, 11B) and each of the at least one magnetic set having two magnetic elements respectively located on opposite sides of the flywheel; a manual adjustment assembly mounted on the frame; and an electronic adjustment assembly (30A, 30B) mounted on the frame and having a linearly movable component moving linearly relative to the frame; and a motor connected to the linearly movable component and selectively driving the linearly movable component to move linearly and push the mounting seat (11A, 11B) of the resistance assembly (10A, 10B) to simultaneously make the brake pad abut against the flywheel and make the at least one magnetic set approach the flywheel; and a linearly movable component moving linearly relative to the frame; and a motor connected to the linearly movable component and selectively driving the linearly movable component to move linearly and push the mounting seat (11A, 11B) of the resistance assembly (10A, 10B) to simultaneously make the brake pad abut against the flywheel and make the at least one magnetic set approach the flywheel; and the resistance assembly (10A, 10B) further has a restoring spring mounted on the frame and connected to the mounting seat (11A, 11B), the restoring spring being capable of driving the mounting seat (11A, 11B) to return to an original position; the hybrid resistance adjustment system characterized in that: the manual adjustment assembly has a shaft being linearly movable relative to the frame and selectively pushing the mounting seat (11A, 11B) of the resistance assembly (10A, 10B) directly to simultaneously make the brake pad abut against the flywheel and make the at least one magnetic set approach the flywheel.