Preparation and deproteinization methods of polysaccharide from garlic (Allium sativum L.) were studied. The crude polysaccharide was prepared by the method of hot water extraction. The percentages of deproteinization and polysaccharide loss were compared as indexes using the hydrochloric acid (HCl) method, trichloroacetic acid method, NaCl method and CaCl(2) method, respectively. The infrared spectra analysis and content analysis showed that the HCl method exhibited the highest percentage of deproteinization, and a little higher percentage of polysaccharide loss than the other three methods. The CaCl(2) method exceeded NaCl method in deproteinization.