The invention discloses a permanent magnetic speed regulation, brake or load apparatus capable of stepless adjustment of magnetic field intensity. The apparatus is characterized in that the apparatus is a of single-rotating disk/multi-rotating disk type structure , a single-rotating cylinder/multi-rotating cylinder type structure, a rotating disk and rotating cylinder combination type structure or a rotating disk and rotating cylinder compound structure, and is mainly composed of a driving rotor, a driven rotor, a work magnetic coupling air gap/medium, a magnetic leakage magnetic circuit/air gap, a magnetic leakage magnetic circuit air gap adjusting disc and an adjusting mechanism. The apparatus provided by the invention is applied to such technical fields as coupling transmission, load speed regulation, automatic transmission, brake and braking, load rotation, power cut-off/combination, motor energy conservation, a household electrical appliance (including an air conditioner, an electric fan and a washing machine) and the like. The technical scheme is used for designing and manufacturing a permanent magnetic speed regulator, a speed regulation shaft coupling, an automatic transmission, a braking device, a load/loading device, a centrifugation load speed regulator or a clutch or a novel energy-saving household electrical appliance.