With the improvement of people’s living standard, the demand for electric energy is increasingly strong. In order to meet the increasing load, the construction scale of power transmission and transformation project of power grid company is increasing, and the difficulty of progress control of power transmission and transformation project is increasing. In order to control the progress of power transmission and transformation projects, it is necessary to make an accurate and reasonable time prediction to make a realistic and feasible schedule. Firstly, this paper analyses the influencing factors of the construction period of power transmission and transformation projects, and determines the key decision factors. Based on the support vector machine method, a prediction model of the construction period of power transmission and transformation projects is established. The prediction accuracy reaches 95.50%, with high accuracy.