The invention discloses a power network voltage regulation and control system and method for wind power generation. The system comprises a first reactive power compensation device, a second reactive power compensation device, a third reactive power compensation device, a first tap gear, a second tap gear, a collection device and a substation monitoring device, wherein the first reactive power compensation device is arranged on a high-voltage side bus of a regional master station connected with a wind power plant; the second reactive power compensation device is arranged on a medium-low voltage side bus of the regional master station; the third reactive power compensation device is arranged on a medium-low voltage side bus of a regional slave station connected with the regional master station; the first tap gear is located on the regional master station; the second tap gears are located on the regional slave station; the collection device is used for collecting a voltage parameter and a power factor parameter in a wind power grid; and the substation monitoring device is used for controlling the corresponding tap gears and/or reactive power compensation devices to be switched according to the voltage parameter and the power factor parameter collected by the collection device. The reactive power adjustment ability of the regional power grid is improved under the condition that a power transmission line from wind power to a substation is relatively long; and the switching frequencies of the reactive power compensation devices are reduced.