Deterioration of stone is a combined process caused by physical, chemical and biological factors especially, microbial growth. Various microorganisms are playing a key role in the weathering of historical artifacts, buildings, and monuments made of granite, marble, and other dimension stones. In this study, the biodeterioration of three types granite, Blue Pearl from Norway, Pergamon Grey from Turkey, and Rosa Porrino from Spain were studied for thirty days under laboratory conditions. The results showed that two of the granite surfaces, Pergamon Grey and Rosa Porrino, supported a heavy colonization of phototrophic microbial consortia. These results also showed that filamentous phototrophic microorganisms were dominant on the surfaces of the granites and indicated that the porosity, the availability of water and chemical composition of the granite have encouraged colonization and caused modification on the surfaces. The filamentous aggregates, possibly calcified fibrillar bodies in the inner parts of granites were also detected by SEM studies.