Abstract: To reduce the pressure pulsation and self-noise of a blade, a hybrid method combining LES and FW-H was used to numerically simulate the blade with the Reynolds number of 2×10⁵ at an attack angle of 5°, so as to study the mechanism of noise reduction and analyze the transient flow field and sound field characteristics of the leading edge blade with root-planed wave teeth. Results show that the root-planed wave teeth accelerate the fluid flow at the leading edge of blade, which can better regulate the flow field and reduce the separation vortex, while the thickness of the wake vortex becomes smaller, and the large-scale vortex breaks into small-scale vortexes in the progress of extrusion and stretching, when the vortex structure gets more compact. The leading edge structure of root-planed wave teeth reduces the pressure pulsation on the blade surface, which has good effects on noise reduction, exhibiting broadband characteristics at low and medium frequencies, with a reduction in total sound pressure level by up to 9 dB.