The water extraction of vegetal polysaccharose from the fruit of Chinese wolfberry, red jujube, flower mushroom, sweet potato and huaishan, the optimization of extracting conditions by orthogonal design and the multiplication of bifidobacterium functioned by polysaccharose extracted from vegetable were studied. The results showed that the optimal extracting conditions of vegetal polysaccharose are as follows: the adding ratio of water, for the fruit of Chinese wolfberry and red jujube is 1∶10, flower mushroom is 1∶15, sweet potato is 1∶3 and huaisan is 1∶9, the temperature of extraction: is 80～95 ℃, the time of extraction: is 1～3 h.In the conditions, the extraction rates of vegetal polysaccharose are: wolfberry 51 8%, red jujube 53.2%, flower mushroom 28.2%, sweet potato 18.8%, huaishan 18.3%. The multiplication of bifidobacterium functioned by polysaccharose extracted from five kinds of vegetal was that the growth rate constant (R) is raised by 135%～85% and the generation time (G) is reduced 56%～44% in logarithmic phase.