The invention provides a method which can estimate the forest leaf-area index by means of ground 
laser point cloud data based on a 
point cloud hemisphere slice and belongs to the research field of a forest 
canopy structure parameter acquisition method. The method includes the following steps of: acquiring three-dimensional 
laser point cloud data of a 
vegetation canopy, and performing pretreatment on the three-dimensional 
laser point 
cloud data; automatically dividing the point 
cloud data into three types including the point 
cloud data of a 
photosynthesis canopy part (e.g. leaves and flowers), the point cloud data of a non-
photosynthesis canopy part (e.g. trunks and branches) and the point cloud data of a bare land, based on a local set feature method; researching 
spatial distribution forms of the point cloud data of the 
photosynthesis canopy part and the point cloud data of the non-photosynthesis canopy part in a three-dimensional space according to a radial hemisphere point cloud slice 
algorithm, and calculating the angle 
porosity; calculating the 
extinction coefficient; extracting the effective leaf-area index; and evaluating a contribution value of a 
xylem part to calculation of the forest angle 
porosity and the forest effective leaf-area index according to a laser point 
cloud point-to-point 
classification result. The result show that: according to the ground laser point cloud data, the contribution rate of the 
xylem part to the effective leaf-area index is 19% to 54% in forests with different densities; and the correlation between the effective leaf-area index calculated by the method and the effective leaf-area index calculated through a fish-eye camera, reaches 74.27%. The method for estimating forest leaf-area index based on the point cloud hemisphere slice enriches the application that the ground laser point cloud data is used to extract a forest canopy three-dimensional structure and bio-physical parameters.