This paper reports results of study on the contents of proteins, amino acids, polysaccharose and uronic acids in 30 species of macroalgae from Shicao, Heishijiao, Shimiao, and Xiaofujiazhuang in the vicinity of Dalian City, N.E.China. The results showed that the protein contents of the 30 algae from highest (112.55 μ g/ml) to the lowest (0.24 μg/ml) was in the descending order ofDictyopteris ndalata, Gelidium vagum, Gymnogongrus japonican, Ectocarpus confervoides, Tinocladia crassa, Sargassum thunberii. In general, the protein content in red algae was higher than that in brown algae. The content of free amino acids showed no significent differences from 7.44 μg/ml4.96 μg/ml in all these algae, in the descending order ofGymnogongrus japonican, Sargassum confusum, Undoria pinnatifida, Laminaria japonica andEctocarpus confervoides. The content of polysaccharose varied from 168.2 μ/ml-22.15 μg/ml in the descending order ofSymphocladia latiuscula, Scytosiphon lomentarius, Desmarestia viridis., Tinocladia crassa, Gracilaria asiatica andPorphyra yezoensis. The content of uronic acids is from 196.24μg/ml-20.77 μg/ml in the descending order ofUlva lactuca, Symphyoclaldia latiuscula, Scytosiphon lomentarius, Ceramimum kodoi, Gracilaria vemucosa andPorphyra yezoensis. The fatty acids in 30 species of algae belong to Rhodophyta, Chlorophyta and Phaeophyta. Most phaeophytes have many (4–12) types of fatty acids.