Abstract: The best coarse grain for compounding with Porphyra yezoensis was selected through the screening of coarse grains for the research about measurement of hypolipidemic functional indexes such as oil absorption and lipase.Firstly,Response Surface Methodology was used to optimize the extraction process of soluble polysaccharides from Porphyra yezoensis by ultrasonic wave. Secondly,the best kind was selected from nine different kinds of coarse grains. Thirdly,the oil absorption capacity in vitro was noticed as the index to screen out the optimum compound ratio of Porphyra yezoensis polysaccharide and coarse grains polysaccharide. Finally,the inhibitory activity of mouse lipase was tested using a compound. The results showed that the optimum extraction technology of Porphyra yezoensis polysaccharides by ultrasonic method was as follows:Material-liquid ratio 1:25,ultrasonic power 150 W,ultrasonic temperature 60 ℃,ultrasonic time 30 min,and the extraction rate of water-soluble polysaccharides was 4.24%±0.19%. Among 9 kinds of coarse grains,coix seed was the most suitable for compounding with Porphyra yezoensis polysaccharide,and the optimum ratio was 1:1.The maximum oil absorption was 45.87%±5.27%. The inhibition rate to mouse lipase was 34.67%. This study provided experimental basis for the development of a new type functional food for reducing blood lipid of Porphyra yezoensis in Bohai Sea.