Mold infestation problems in building are a complex phenomenon due to various causes such as environmental conditions including temperature and relative humidity, substrates (building materials), exposure time, and so on. Earlier studies showed the interrelationship among humidity, temperature conditions and mold growth. However, surface structure also can be a key factor to mold germination. This study conducted experiments on the mold germination and growth on wallpapers with different surface structures. Four wallpapers and two fungal species (Aspergillus versicolor, Penicillium chrysogenum) were selected for experiment and observed fungal germination and growth on the different surface structures of wallpapers using scanning electron microscope. The results showed that the shape of the micro structure of wallpaper surface affected to the growth of fungi. Keywords：Building material, Wallpaper, Surface structure, Mold, Scanning electron microscope