To provide a wind turbine generator capable of creating an air flow which can efficiently circulate air between the interior of a cover and a nacelle so that the interior of the cover can be efficiently cooled down. A wind turbine generator (1) is provided with a rotor head (4) to which wind turbine blades (6) are attached, a cover (5) which covers the rotor head (4), and a nacelle (3) which accommodates a power generating facility (7) connected to the rotor head (4), and has an air circulation between the interior of the cover (5) and the interior of the nacelle (3), wherein an air flow creation device (20) which creates an air flow is provided inside the cover (5).
