The invention belongs to the technical field of clutches and particularly relates to an adjustable speed-variable torque clutch based on gears. The adjustable speed-variable torque clutch based on the gears comprises an input shaft, an installation shell, friction disks, electromagnetic drive blocks, electromagnetic adjustment plates, electromagnetic supporting plates, supporting rods, compression springs, drive supports and a support connection plate. When the input shaft rotates, if third transmission gears are required to transmit torque, the support connection plate and the electromagnetic adjustment plates are controlled to enable an output shaft to rotate by 180 degrees when the input shaft rotates by 360 degrees; if second transmission gears are required to transmit the torque, the support connection plate and the electromagnetic adjustment plates are controlled to enable the output shaft to rotate by 360 degrees when the input shaft rotates by 360 degrees; if first transmission gears are required to transmit the torque, the support connection plate and the electromagnetic adjustment plates are controlled to enable the output shaft to rotate by 720 degrees when the input shaft rotates by 360 degrees. Under the condition that the input torque of the input shaft is not changed, through change of the position of the support connection plate, the torque transmitted by the output shaft can be adjusted.