In this paper, the influence of cultivar, season and procedure on Oolong tea polysccharide content, components and biological activities was studied. Besides, immunity mechanism of tea polysaccharide with high activity was assayed. 1. Cultivar, season and process could influence the content, compositions and biological activity of Oolong tea polysaccharide(OTPS).The content of polysaccharide in Oolong tea made with cultivar DaYeOolong was superior to that of cultivar FuDingDaBai, and uronic acid and pro...