To characterize the polysaccharides which exist as soluble forms in Korean traditional alcoholic beverages, the polysaccharides were isolated from Korean pear wine and their anti-complementary activities were examined. The main polysaccharide, PW-1 was purified to homogeneity from the crude polysaccharide (PW-0) in pear wine by size exclusion chromatography using Sephadex G-75. Molecular mass of PW-1 was estimated to be 150 kDa and it contained significant proportion of mannose (81.8%) and 5 different minor component sugars such as arabinose (1.2%), galactose (2.7%), glucose (8.5%), galacturonic acid (5.3%) and glucuronic acid (0.5%). These analyses indicated that the main polysaccharide in pear wine was mainly present as a mannan which had originated from the cell walls of fermenting yeasts. On the other hand, PW-1 showed potent anti-complementary activity in a dose-dependent fashion. Identification of C3 activation products by the crossed immunoelectrophoresis using anti-human C3 and anti-complementary activity of PW-1 in $Ca^{++}$-free condition suggested complement activations by PW-1 from Korean pear wine occur via both classical and alternative pathways.