Abstract: To Study the relationship between tissue structure of cut shreds and moisture retentivity thereof,the surface and sectional structures of flue-cured,burley and oriental tobacco shreds were observed by a scanning electron microscope,the stomas of under epidermis were observed by an optical microscope,and the capillary specific surface area was measured by a specific surface area tester.The results showed that:1) The structure of oriental tobacco was the closest and its section was of porous structure,the section of domestic and Zimbabwean flue-cured tobacco was opener.2) The stoma number of burley tobacco was higher than that of flue-cured tobacco,while lower than that of oriental tobacco.The stalk positions of flue-cured tobacco of the same variety in the order of specific surface area were middle >lower >upper.3) The tissue structure positively correlated to equilibrium moisture content of tobacco shreds in low humidity(RH=30%) environment,while their correlation became negative in high humidity environment(RH=60%);and the influence of surface chemical composition in tobacco shreds on moisture content increased gradually with the rise of relative humidity.