In presence of wind, the DC space charge undergoes a new migration motion to change the ground electric field distribution characteristics. The measurement of DC total electric field is generally required in a good weather condition with wind’s speed less than 2 m/s, no rain, no snow and no fog. However, in the actual measurement process, the wind whose speed is less than 2m/s still changes the distribution of the spatial ion flow field, which affects the measurement. In this paper, the upstream finite element method is used to simulate the ion flow field distribution of wind’s speed less than 2m/s. And it is concluded that the total electric field also changes greatly with wind’s speed less than 2m/s. By using 29 field mills, the total electric field of a ±800kV DC transmission line from Ningdong to Zhejiang was continuously monitored for 12 hours. The wind direction and speed were recorded, and the correlation between the measurement and the wind direction were analysed. A method using the average value of the lateral wind speed as the wind condition was proposed, which had higher accuracy than regardless of wind. When there is no real-time monitoring of wind speed, the measured value can be predicted using ± 2m/s as the wind speed condition to envelope the measured value.