A multifunction electromechanical device for an aircraft undercarriage. The device comprises a first shaft (10) mounted to rotate on the aircraft about an axis of rotation (R) that is substantially parallel to a hinge axis (X) of the undercarriage relative to the aircraft and a telescopic second shaft (20) mounted to rotate on the undercarriage extending downwards to the proximity of the wheels carried thereby. The device also includes a transmission (19) for transmitting rotary motion from the first shaft to the second shaft and a transmission (21) for transmitting rotary motion from the second shaft to at least one wheel carried by the undercarriage. With this configuration, if the wheel is not fitted with a brake, there is a specific brake (30) for braking one of the shafts relative to the undercarriage, and a motor (11, 15) for causing the first shaft to rotate.