The incubation period of active-guinea pig anaphylaxis was studied by antigen-antibody dilution method of Ogata. The results were as follows. 1. The small amount of precipitin was produced in guinea pig injected by small amount of antigen, and the typical faetal anaphylaxis proved least within 10 days after injection. 2. Though the typical foetal anaphylaxis was induced 0.5 or 1ml., the severer schock was elicited in guinea pig sensitized 1.0 ml. compared with 0.5 ml. 3. No great difference of antibody production and the incubations period between the method of 2 times succesive injection in guinea pig subctan and the 1 time injection with same quantity could not be found. 4. The production of precipitin was proved an increase propotion to the sensitized antigen quantity and the strength of anaphylaxtic schock was propotional to the antibody titer. 5. It was found out that the sensitized effect of guinea pig injected small amount of antigen to show weaker in the order of intravenous, intraperitoneal and subctaneous method, in derees of reactivity according as the increasing amount of sensitized antigen upper relation seems to become less distinct. 6. Decreasing grad of the temperature was propotional to the strength of anaphylaxis. 7. There could be found no great, pifference in the anaphylaxtie schock due to the body weight.