Abstract: Aiming at the problem that the hidden trouble of tree barrier seriously threatens the safe operation of distribution lines, the typical tree species in the corridor of distribution lines in Guangdong area are investigated and studied. First, a tree height growth prediction model based on Richard’s equation is established, and the correlation deviation test results show that the model is of high accuracy and can accurately predict the tree height in a certain period in future. Then in cembination with a wire sag model, the wire sags under different load conditions are calculated. Finally, a model of clearance between trees and lines is established. By predicting the clearance distance between wire and tree, the functions of real-time detection of hidden trouble of tree barrier and risk assessment and prediction of tree barrier are realized, which avoids the flashover fault caused by the excessive growth of trees and the increase of line sag, and ensures the safe and stable operation of distribution lines.