Investigation and study are made on influences of large-scale power service interruption over life, society and economy in the Tokyo metropolitan region. The area of service interruption covers Tokyo Metropolis and Prefectures of Kanagawa, Saitama and Chiba, and approximately 11.5 million households or 32 million people. Presumed for study is a case where the service interruption will continue for three days starting 1300 hours on Monday in late August, and during those three days the interruption will be restored by 1/3 a day. As for home life, households are largely affected not only by home electric appliances not in operation, but by malfunction of social infrastructure: interruption of water and city gas supply in cooking, paralyzation of mass media in telecommunication, paralyzation of trains in moving, difficult food storage, closure of banks and supermarkets in the consumer section, and also malfunction of the police, fire service and medical facilities affecting safety, sanitation and existence. In economical evaluation, simulation on those effects is conducted, and in macro evaluation, the amount of the damage caused by service interruption is estimated approximately 1.8 trillion yen per year. 126 refs., 63 figs., 109 tabs.