Hyperlipidemia is a major risk factor for heart disease that represents a major problem and public health burden. As a result, this lead us to assess the potential of polysaccharides isolated from Ulva fasciata as hypocholesterimic source on rats fed hypercholesterolemic diet using fluvastatin as reference drug. Also, the physico-chemical characterizations of isolated polysaccharides were investigated. The cold and hot polysaccharide extracts consisted of ash (9.80 and 5.71%w/w), sulphate (14.6 and 19.3% w/w), uronic acid (2.9 and 2.0% w/w), sugar (41.27 and 46.00%w/w) and protein (15.63 and 36.25% w/w). The cold water extract composed mainly rhamnose, xylose, galactose, arabinose while fucose, xylose, rhamnose, glucose, arabinose, were found as the major sugars of hot water extract. Fourteen and fifteen amino acids could be identified in cold and hot polysaccharide extracts, respectively, aspartic and glutamic acids were found to be the predominant amino acids in both polysaccharides. The isolated polysaccharides could significantly reduce concentrations of total cholesterol, triglycerides and low density lipoprotein in the serum of hyerlipidemic rats while, significantly increase the level of high density lipoprotein. The polysaccharides isolated from Ulva fasciata act as natural hypocholesterimic source.