It is important for the study of the atmosphere-vegetation interaction to extract architectural parameters rapidly and accurately.In this paper,the methods for leaf area index(LAI) and leaf angle distribution(LAD) retrieval areaddressed from the following three aspects:the theory and model of canopy structure parameters extraction,the retrieval of gap fraction,and clumping index.And the main factors affecting the retrieval accuracy of canopy parameters in the collection and analysis of fisheye photographs and model's hypothesis etc are also ananyzed.It is worth pointing out that the hemispherical photography is an ideal indirect LAI and LAD estimation device,while errors from digital hemispherical canopy photography could not be avoided,therefore,parameter validation should be performed to delete the uncertainty in retrieval results.