The invention discloses a myrtle polysaccharide P1, the separation method thereof and the use in preparing hypolipidemic drugs therefor, wherein the P1 contains 6.74% of ribose, 1.73% of rhamnose, 60.06% of arabinose, 3.54% of xylose, 5.64% of mannose, 13.16% of glucose, and 9.13% of galactose. The experiment result shows that the myrtle polysaccharide P1 has a certain ability to bind cholate in vitro. Taking cholestyramine as a positive control and the binding rate of cholestyramine to each cholate as 100%, the relative binding rate of the myrtle polysaccharide P1 to sodium taurocholate, sodium glycocholate and sodium cholate was 25.28%, 44.56%, and 50.10%, respectively.