Abstract: Gearbox is an important component of wind turbine, which directly determines wind farm revenue. It is of great significance to gearbox operational status evaluation by analyzing vibration signals. The structure and failure characteristics of wind turbine gearbox are discussed first. According to characteristics of one type of wind turbine gearbox, schemes for vibration data acquisition are established and high-speed shaft vibration signals from two wind turbine gearboxes are collected. Comparative analysis is performed by using Hilbert energy spectrum and short-time Fourier spectrum rearrangement methods to extract fault characteristic frequency from high-speed shaft measuring point vibration signal on two wind turbine gearboxes. Analysis results indicate that one gearbox has high-speed shaft damage which is verified by field test. The result confirms validity and practicability of combination of Hilbert energy spectrum and short-time Fourier spectrum rearrangement methods in extraction of wind turbine gearbox fault characteristic frequency.