Collapse accidents of transmission tower-line systems under typhoon occur frequently. Here, the extreme wind speed and wind profile index were simulated using Monte-Carlo method and YanMeng typhoon field, the fluctuating wind of typhoon was calculated using Shiyuan typhoon spectrum. A model consisting of one tower and two-span conductors was established with the FE software ANSYS, and the wind load effect of the model was calculated under typhoon wind load. The analysis indicated that the wind load of conductors and ground wires make a significant contribution to the axial force of principal members, the contribution rate reaches 58.9% during extreme value status of typhoon; the damage due to typhoon can be reduced through appropriately decreasing span distance or dropping lines to protect towers in typhoon region; the dynamic responses of the model during extreme value status of typhoon are much larger than those of the model during the equivalent static wind status due to high strength and high turbulence’s characteristics of typhoon; the adjustment coefficient of wind load in the existing design code seems to be smaller, its dynamic amplification effect must be fully considered under typhoon condition.