A total of 222 species of algae were collected Irom the salt lake area in Yuncheng, Shan xi Province, North China, representing 5 didivisions, 30families and 70 genera. Among them 35 speces from 4 families and 17genera in Cyanophyta, 93 speces from 19 families and 40 genera in Chlorophyta, 83 speces from 5 families and 10 genera in Euglenophyta, 2 speces from 1 family and 1 genera in Xanthophyta, 9 speces from 1 family and 2 genera in Charophyta. Concerning the salt concentration of the water, 4 types can be divide, i. e. fresh water(salt concentration < 0. O5 %), mesohalinous water(salt concentration 0. O5%-3%), euhalinous water(salt concentration 3%-4%)and polyhalinous water(salt concentration > 4%).Because of the effect of different salt concentration the difference is evident in the distribution of alage in 4 types of the water.It is shown that the higher salinity, the fewer number of species.