Using the protein, nuclear protein and polysaccharide fractions obtained from old tuberculin by salt analysis or by paperelectrophoresis the author performed the tuberculin reaction and erythrocyte coagulation reaction, and obtained the following results: 1. In the tuberulin reaction conducted in each of the protein, nuclear protein and polysaccharide fractions from old tuberculin the intesnity of the tuberculin reaction has been found in the descending order of protein, nuclear protein, and polysaccharide fractions. In the erythrocyte coagulation reaction the intensity is in the order of polysaccharide, nuclear protein and protein fractions. 2. By the paperelectrophoresis of old tuberculin with ninhybrin reaction phoretic peaks, A, B, C, and D were obtained in the order of phoretic speed. Of them the peak C seems to be dialytic substance. 3. By ammonia silver nitrate reaction two phoretic peaks A' and B' were obtained according to the phoretic speed. 4. After the paperelectrophoresis of old tuberculin and making l cm strips each from the starting point, when the fractions are extracted by physiological saline solution, the further away from the starting point the lighter is the color. Moreover, the tuberculin reaction and erythrocyte coagulation reaction likewise grow weaker as the distance is further away from the starting point, but there seems to be no marked correlation among the three tests.