The invention relates to a wind turbine comprising a rotor shaft (11), a multiplier (3) with at least one planetary-type stage and a generator inside a frame (1). The inventive turbine also comprises a first tubular casing (13) which is solidly connected to the frame (1) and which houses the rotor shaft (11). According to the invention, one end of the rotor shaft is solidly connected to the hub of the rotor, while the other end thereof is solidly connected to the planet carrier (21) of the multiplier unit. The aforementioned first casing includes a bearing (15) for supporting the rotor shaft (11). The invention also comprises a second casing (17) which is equipped with a bearing (19) for supporting the planet holder (21), one end of said second casing being solidly connected to the crown gear of the first planetary stage of the multiplier unit (3) and the other end thereof being solidly connected to the first casing (13) and to the structure of the frame (1).