This article deals with one of the major social problems in Japan which sociologists have both individually and systematically paid little attention to : the increase of multiple-debtors, those who borrow money from various kinds of lenders. This article aims to provide a broader contextual picture behind this social problem, from which further empirical investigation can be carried out. I have collected and analyzed the available statistical data from three main sources : creditors, borrowers, and court records. In my conclusion, I suggest that we specify the conditions and processes of the problematic situation. Firstly, I examine the development of the consumer credit market, based on the data from the annual report "Consumer Credit Statistics of Japan", edited by the Japan Consumer Credit Industry Association. Consumer credit institutions have succeeded in granting large sums of credit, particularly since the oil crisis of the mid-1970's, focusing on high-interest consumer finance. As a result, outstanding credit has grown into a large burden of debt on consumers. Secondly, I make a chronological and cross-sectional analysis of borrowers by using the Annual Report on National Accounts and the Annual Report on the Family Income and Expenditure Survey, both published by the Japanese Government. The use of credit has spread rapidly throughout national households, in contrast to the decrease in disposable income and savings. A large propotion of many peoples' income is now used to pay off debt, such as housing loans, loan repayment installments, revolving and lump sum credit, consumer finance and so on. Thirdly, I clarify the recent growth of consumer bankruptcy, referring to the public records from the Annual Report of Judicial Statistics, issued by the Japanese Supreme Court. Using this data, this article shows various trends over the course of the last five decades. It demonstrates for the initial period that the total number of bankruptcy petitions did not pass ten thousand before the early 1980's. By contrast, although a slight decrease can be observed in the data for the mid and late 1980's, the data for the 1990's portrays a steady rise, peaking with the figure for 1996,when more than fifty thousand petitions were filed. Finally, after contextualizing the increase of these multiple-debtors into the three trends as stated above on a macro-quantitative level, I conclude that the research in this area needs to move away from the simple explanation of this social problem in terms of individual skills as regards money management, and move onto the specification of the conditions and processes under which people get into trouble with debt, as well as how the system of credit has developed during the postwar period.