Wind turbine blade with split winglet at apex

The invention relates to a wind turbine blade with a split winglet at the apex, which belongs to the field of wind power generation and comprises a winglet (1), a root connecting part (2) and a main blade (3), wherein the winglet (1) is composed of n sub wings, n is 2 or 3, and all the sub wings are trapezoid-shaped with the same taper and sweepback (12), the n sub wings are provided with different anhedrals; the root connecting part (2) extends out of a main blade apex (11) and is an irregular sphere in shape by taking the wing section of the main blade apex as the standard; the irregular sphere wraps the main blade apex (11) and is connected with the sub wings. According to the invention, the spanwise flow of the blade apex can be reduced, the vortice density of the blade apex without the winglet is dispersed, the induced resistance exerted by the blade apex vortex to the blade is weakened, and the purposes of improving the aerodynamic performance of the wind turbine and restraining the effect of the blade vortex in wake flow are realized, so that the aerodynamic performance is brought into play to the greatest degree.