Abstract: Through investigation of intertidal benthic macro\|algae in ten sections of southern Zhejiang from autumn of 2006 to spring of 2007, we have collected 61 species of benthic macro\|algae and analyzed the flora characteristic of the spatiotemporal distribution of the benthic algae. The seasonal succession in species composition of benthic algae was very obvious in the inter\|tide of southern Zhejiang. According to published results, among the 61 species of benthic macro-algae investigated in southern Zhejiang, 51 species have medical values. The algae showed medical effects against diseases such as tumor, virus, cardiovascular disease, edema, hypertension, fever and poisoning and some could act as insecticides. The purpose of this study is to provide scientific basis for the protection, the sustainable development and utilization of macro-algae．

Key words: southern Zhejiang, benthic macro-algae, biomass, medical values