The hawthorn polysaccharide was extraction with the method of hot bath,and was put into the growth test of Lactobacillus bulgaricus.And with the help of orthogonal experimental design,extraction condition was optimized.The results showed that with the optimized conditions,that solid-liquid ratio of 1: 20,time of 6h,the temperature at 90℃,the polysaccharide yield was up to 3.92%.The Hawthorn polysaccharide had growth-promoting effect on Lactobacillus bulgaricus most when polysaccharide ratio of 2%,pH value 6.5,temperature of 42℃.By comparing the growth curves,it showed hawthorn polysaccharide had obvious positive effect on Lactobacillus bulgaricus.