Wind turbine blades made of composite materials at the end of their life cycle become the waste very difficult for final utilization. There are three possible routes for dismantled wind mill wings: landfill, incineration or recycling. In the paper the method of recycling of waste glass fiber reinforced plastic, coming from used wind turbine blades with microwave pyrolysis is described. Microwave pyrolysis of the fragmented blade from a wind mill blades were carried out at 300 to 600ºC in nitrogen atmosphere in special reactor at Stena AG facilities. The pyrolysis generated gas, oil and recovered glass fibres. The hydrocarbon pyrolysis products were analysed in terms of chemical composition and energy content while the recovered glass fibres were used to produce new thermoset composites. Further developments on pilot plants are in progress.