Tight sandstone are formed in various sedimentary environment，the relationship between porosity and permeability of tight sandstone is complex，and the pore throat structure is the key parameter for reservoir characterization and evaluation. Taking Paleogene tight sandstone in Jiyang Depression as an example，the petrologic features and pore throat structures of different sedimentary types were studied and then the classification scheme of tight sandstone based on petrologic features and pore throat structure characteristics was proposed by means of systematic cluster analysis. Results indicate that petrologic features and pore throat structure of turbidity sandstone，beach-bar sandstone and delta-front sandstone are similar. The average pore throat radius of type Ⅰ best reservoir，type Ⅱ good reservoir，type Ⅲ normal reservoir and type Ⅳ worst reservoir are greater than 1.1，0.7-1.1，0.4-0.7，less than 0.4 μm，respectively. The sandstone with pore throat radius less than 0.3 μm cannot be regarded as reservoir. The tight glutenite is obviously different from the former three types of tight sandstone，for tight glutenite，the average pore throat radius of type Ⅰ best reservoir，type Ⅱ good reservoir，type Ⅲ normal reservoir and type Ⅳ worst reservoir satisfies greater than 1.3，0.8-1.3，0.3-0.8，less than 0.3 μm，respectively.