Abstract: An investigation has been made on the fresh-water Algae Huashan. The author has collected 134 species, varieties and forms belonging to Bacillariophyta. Some salient features are given below:The diatom florae are rich in this region There are 74 general species and 38 special mountain species.Predominant diatoms in this region consist of the following species: Melosira varians, Cyclotella shanxiensis, Diatoma vulgare and its var, producta, D. hiemale var. mesodon, Meridion circulate and its var. constricta, Ceratoneis arcus and its var. amphioxys, Fragilaria construens, Synedra ulna, Navicula graciloides, N. Cryptocephala var. veneta, Cymbella turgidula, Gonphonema acuminatum var. trigonocephala, G. constrictum, G. gracile, Cocconeis placentula var. euglypta, Achnanthes biasolettiana, A. conspicua var. brevistriara, Nitzschia amphibia, N. palea, N. gandersheimiensis. These diatoms are not only comparatively widespread but also outnumbering the rest in the samples.The diatom florae vary with different water bodies. These diatoms are Biological indicators and monitors of water organic pollution.