《Guidelines for electrical transmission line structural loading》(ASCE 74—2009) is widely applied and used for reference in many countries over the world, which is very important to the electric power construction in our country and foreign projects. Wind load is the control load for transmission tower. So it is necessary to master the differences of wind load computation methods between Chinese code and ASCE 74—2009. This paper introduced the wind load computation formula for transmission tower by Chinese code and ASCE 74—2009, and detailedly compared the differences of basic wind speed, height variation factor of wind pressure, shape factor, wind load factor, topographic factor, icing load factor, yawed wind load computation method and so on. The results can be used as a reference for the technicians of transmission line engineering.