Tumor-bearing animals were administered with /sup 67/Ga citrate and tumor homogenates, from which nuclear fraction was removed, and mitochondrial fraction of the host livers were digested with protease (pronase P). After digestion, the supernatants of the reaction mixtures were applied to a Sephadex G-100 column. Resultant eluates were analyzed for radioactivity, protein, uronic acid and sialic acids. Three peaks of radioactivity were obtained by gel filtration. The first peak eluted in the void volume contained a species whose molecular weight exceeded 40,000. The second peak consisted of substances with molecular weights of 9400-40,000. Radioactivity in the third peak was from liberated gallium-67. /sup 67/Ga in the second peak was bound to acid mucopolysaccharide and/or the sulfated carbohydrate chain of sulfated glycoprotein. It was thought that /sup 67/Ga in the first peak might be bound to some acid mucopolysaccharides. Considering the results of cellulose acetate electrophoresis, /sup 67/Ga in the second peak seemed to be bound to acid mucopolysaccharide which contained no uronic acids, and/or to the sulfated carbohydrate chain of sulfated glycoprotein. It was concluded that /sup 67/Ga was bound to the acid mucopolysaccharides and/or the sulfated carbohydrate chain of sulfated glycoprotein in tumor tissues and liver lysosomes.