This paper introduces a method based on the Electro-Geometrical-Method (EGM) to determine the number of direct lightning strikes on a wind turbine considering the change of blade height due to rotation. Different types of turbine installed in areas with various flash densities in Vietnam were used to compute the number of stroke. When comparing with lEG method, it was shown that the number of direct stroke to wind turbines determined by EGM method is higher than that determined by lEG, especially for the wind turbines higher than 110 m and areas with high flash density. Thus, it is suggested that EGM method should be used to determine the number of direct stroke to wind turbines for lightning protection purposes.