Biomass (Chl.a) of benthic algae colonized and developed mature community on different artificial substrata was determined in eutrophic lake Donghu, and species composed and structure characteristic of mature diatom communities on artificial and natural substratum were analysed qualitatively. Biomass variance of benthic algae was compared on four different artificial substratum, granite stone, glass, plastic (PVC) and pine wood during the colonization period, and the peak biomass of benthic algae (Chl.a, 71.0μg/cm²) on PVC was significantly higher than that of the other artificial substrata, which showed PVC was the most suitable artificial substratum for benthic algae. Species composition, dominant species, similarity index and diversity index of benthic diatom communities showed a relatively high degree of consistency between natural and granite artificial samplers, which suggested granite should be the most favourable artificial substratum with benthic algae used as indicatory biology that monitored and evaluated water quality.