Abstract: Wind load is the main controlling load in the design of transmission line. The wind load adjustment coefficient is adopted for computing wire load in China’s code. However, the physical meaning of the coefficient is not clear in the code. Based on the wind engineering theory, a formula is deduced for calculating the gust response coefficient of wire, and parameters are chosen to calculate the value. Compared with the coefficients designated in such codes as China’s code, ASCE 74, BS EN 50341 and IEC 60826, the calculated coeffficient with the deduced formula is close to the designated value of ASCE 74, BS EN 50341 and IEC 60826. While the effects of fluctuating wind is not considered in China’s code, the wire wind load calculated according to China’s code is lower than the real load.