A power-split wind power gearbox for transmitting a torque generated by a rotor hub (1) to an output pinion (12) rotating relatively faster thereto for driving an electric generator, wherein at least two planetary steps (10a, 10b) connected in parallel are provided for a gear internal power-split gear multiplication, wherein furthermore the coupling of the rotor hub (1) occurs by means of the connecting ring element (2) on the gearbox input side, the element being supported rotatably by means of a large antifriction bearing (5) on a rotationally fixed gearbox housing (3) and transmitting the power flux in a power-splitting manner to the sun gears (6a, 6b) of the planetary steps (10a, 10b), which are connected in parallel, via cardanic decoupling means configured thereon.