<p>Provided is a wind turbine generator including an electric pitch-control device that efficiently utilizes the entire circumferential teeth of a ring gear (11) of a wind turbine blade so as to eliminate the need for work at high elevation using a crane or the like even when the teeth of the ring gear (11) are partly broken. A wind turbine generator having an electric pitch-control device that performs pitch-angle control by using a motor to drive a pinion gear (12) that meshes with a ring gear (11) of a wind turbine blade includes a plurality of pinion-driving-mechanism securing supporters (20) or a fixing/releasing switching part (30) as a meshing-region changing mechanism that changes a pitch-angle-control meshing region of the ring gear (11) that meshes with the pinion gear (12) during the pitch-angle control.</p>
