The invention discloses a construction method for a virtual anemometer tower for a wind power plant. The construction method comprises the steps of 1, collecting basic data and historical data of n fans in the wind power plant; 2, collecting real-time data of the n fans in the wind power plant; 3, performing simulation and calculation on wind speed and wind direction at the overall wind power plant hub height at the moment according to the historical data and the real-time data of the n fans in the wind power plant; 4, calculating a temperature T- at the overall wind power plant hub height at the moment; 5, calculating the air density, the humidity and air pressure at the moment of the wind power plant; and 6, forming virtual anemometer tower data of the wind power plant at the moment according to the data obtained through calculation. By adoption of the construction method, the problems of poor data quality of the anemometer tower, relatively low wind power prediction precision of the wind power plant and the like caused by the facts as follows are solved: due to special geographic positions and meteorological characteristics of plateaus and mountainous areas, several anemometer towers or fan wind meters data cannot represent the overall wind power plant in the complex landforms in an all-around manner; and collapse of the anemometer tower, damage of the wind testers, and short-term dysfunction are caused by frequent disasters of icing and the like.