Based on the 112 specimens of 28 species from the Chlorophytes, Phaeophytes and Rhodophytes, which were collected from different provinces along the coast of Vietnam were used to determine Protein, Carbohydrate
Lipids, ash contents for use as food, medicine and bio-fuel. Among them, individual differences were important in all of the measured parameters which in turn is likely to effect their ecology and community structure. In most species, the major component was total Carbohydrate (Chlorophytes range at 56.45 +/- 3.29 percent dry weight (dw), Phaeophytes range at 65.81 +/- 5.18 percent dw, Rhodophytes range at 66. 34 +/- 2.41 percent dw. Highest percentages of Protein were found in Chlorophytes (range 15.81 +/- 3.32 percent dw, with significantly lower percentages in Phaeophytes. All species had Lipid contents within the range 2.32-2.62 percent dw, no significant differences between phylum. Most species had moderate to high ash contents 6.20-10.78 percent dw, with significant differences between phylum.