The invention discloses a wind power plant virtual anemometer tower system and method based on a wind turbine generator in a mountainous area. The system comprises a sensor unit of a wind turbine generator. The sensor unit of the wind turbine generator is connected with a wind turbine generator analog-to-digital converter. The wind turbine generator analog-to-digital converter is connected with a wind turbine generator data acquisition and transmitting device. The wind turbine generator data acquisition and transmitting device is connected with a wind power plant monitoring center receiving terminal. The wind power plant monitoring center receiving terminal is connected with a wind power plant monitoring center monitoring background. The difficulty in simply relying on an anemometer tower to represent the wind power of the whole wind power plant, which is caused by poor correlation between the wind data of a single arranged anemometer tower and the actual output of the wind power plant and high cost of anemometer tower installing in the plateau mountain area in the prior art, is solved. The technical problems of serious lack of anemometer tower data and the like, which are caused by damage or short time working failure of an anemometer due to icing or anemometer tower damage or collapse due to special geographical and meteorological conditions in the plateau mountain area, are solved.