Abstract: It is well demonstrated that microbe—mineral interaction plays an important role as a geologic agent in the evolution of epigenetic system．There is a dynamic exchange of elements between microorganisms and minerals，which affects the surface structures of the minerals．The dissolution and crystallization of minerals are remarkably affected by metabolic activities of microorganisms through creating microenvironment at the interface or interaction with metabolic byproducts．As the biomineralization products，the newly formed minerals generally record much information about the influence of microorganisms，which can be evaluated by surface characterization．This paper analyzes the specific area，pore structure，fractal dimension and surface energy of three types of iron sulfates formed by microbiological and abiotic chemical processes，respectively．The results show that schwertmanite and jarosite are formed in the 9 K culture medium due to inoculation of Thiobacillus ferrooxidans；whereas，only jarosite was formed under the abiotic contro1．The particle structure，grain-size distribution and surface energy are quite different between the microbially and abitoically formed minerals．