Compactional shear deformation bands formed in porous sandstone often reduce the rock permeability to a certain extent. The permeability characteristics of deformation band and its surroundings are one of the important contents in the study of deformation bands in porous sandstone. Because the width of a deformation band is often millimeter, the conventional permeability test method can not meet the research needs due to the limitation of resolution. In this paper, the effect of microstructure of deformation bands on permeability is analyzed based on AUTOSCAN with intensive testing function in order to solve this problem. Methods:Single deformation bands, small cluster of deformation bands and medium and large cluster of deformation bands of different sizes in the upper Cretaceous Honghuatao formation of Yuan’an graben are selected as research samples. Based on the detailed study of their microstructure, AUTOSCAN with high- resolution testing function is used for intensive testing, and the continuous permeability profile is established. Results: The test results show that the low permeability points are characterized by drop- down peaks in the permeability line scanning curve, and have a significant corresponding relationship with the deformation bands. There are differences in the range of abnormal low permeability in different deformation bands. The greater the thickness of the deformation bands, the higher the degree of abnormality; The permeability of different microstructural elements decreases differently. The order of permeability from low to high is: central cataclastic bands of large cluster of deformation bands < central cataclastic bands of small cluster of deformation bands < inter band area < central cataclastic band of single deformation band < Marginal transition area < surrounding rock. Conclusions: The analysis shows that although the thickness of deformation bands and the size of permeability detection hole will affect the permeability detection results, the change of rock internal microstructure caused by the formation of deformation band is the essential reason for the decrease of permeability. The central cataclastic bands of medium and large clusters of deformation bands are densely developed, the strain hardening between bands is strong, and the continuity is good in three- dimensional space, which is likely to have a great impact on fluid seepage and oil and gas migration. Due to the poor continuity of a single deformation band, it is difficult to really hinder fluid flow, but will enhance the anisotropy of the whole rock.