To extract the geometric parameters of individual trees, photogrammetry and field methods used in the past. The field method is to manually extract the geometric parameters of individual trees. Also, Aerial photos cannot directly provide information three-dimensional structure of the forest. That's why LIDAR technology is currently widely used. The first step is to extract the geometric parameters of the tree, is separation the points trees of LIDAR data by using Skewness Balancing and Slope Filter algorithms. The second step, With the obtained points trees, Create a linear approximation of the actual shape of trees using triangulation Delauney that it is known alpha form and in general a three-dimensional convex hull is produced from trees, Then doing the separation incorporated trees using Local Maxima and Minima algorithms. Finally, By using 2D closed circle algorithm, Can be calculated geometric parameters tree such as height, diameter of vegetation, trunk diameter, height trunk, tree vegetation height.