The virus, which was isolated and preserved in the same way as that in the preceding report, was used in the present studies. The resistance to disinfectants was determined by observing the establishment of infection in the mice inoculated with the mixtures of virus emulsion and various sorts of disinfectants. The results were as follows: 1) The virus was severely injured by the contact with the common disinfectants, and was inactivated by the only 10 to 15 minutes' contact. 2) The inactivation of virus by the contact with disinfectants came near to completeness in about 3 weeks, though the inactivated virus still caused the pathological changes in some cases. The immunization of animals by thus inactivated virus could give rise to a sufficient immunity in them. This fact gave a important suggestion to the further studies. 3) In some cases, even the virus kept in contact with disinfectants for 4 to 6 weeks still caused some pathological changes. This fact suggested that this virus had a very strong resistance to disinfectants.