Abstract: coal samples from coal seam No.8 of Taiyuan Formation, Hedong coal field, are measured for structure classification, micro-fractal characteristics and fracture densities.The research focused on relationship between lithological struchures and fracture distributions.The results show that the difference of fracture densities in different lithotype bands is large.The fractures mainly distributed in vitrain bands.In vitrain bands the density and fractal dimension of fractures related to the thickness and lithotype of adjecent bands.The study on coal lithostructures is of great significance for predicting the permeability of coal seam.