Abstract: The pyrolysis process of waste wind turbine blades in the simulated flue gas was first studied. The effects of flue gas temperature, pyrolysis time, flue gas composition and heating mode on the quality of recycled fiber were investigated, and the pyrolysis mechanism was also analyzed. The results showed that the resin matrix of wind turbine blade could be carbonized and then vaporized by heating the blade directly with the flue gas, and as a result, a pure glass fiber could be obtained. In this way, the waste blade was recycled. When the blade was pyrolyzed at 420~450℃ for 5~6 hours, the purity of the recycled fiber was above 99%, and its tensile strength decrease was less than 10% compared with the original fiber. During the pyrolysis, the concentration of SO2 in flue gas had little effect on the recovered fiber.