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This article chooses ten kinds of common trees in Beijing as the research objects. A 3D laser scanner was used to get the point cloud data of target trees. The tree crown volume was calculated by using the combined method of cubic lattice method and canopy surface triangulation. The tree factors from point cloud data and the calculated tree crown volume were analyzed to establish the estimation equations of tree crown volume, breast diameter, tree height, average crown height and average crown width. The accuracies of these equations were verified. Taking ginkgo as research object, the test results showed that the tree crown volume of ginkgo was significantly correlated to the breast diameter, tree height, average crown width and crown height. Finally, a three factor (breast diameter, average crown width, crown height) model was selected and verified on tree crown volume prediction of ginkgo. The results showed that the model had a good fitting accuracy of 90.5%. The three factor model was also employed on other species of trees and the results showed it could be used on the prediction of other tree crown volumes.