Bankruptcy is a judicial process purporting to regulate and adjust the financial relationships between debtors and creditors which come into a deadlock. In the modern United States, bankruptcy has become a concept pervading each corner of the social and economic lives. It touches mass tort victims, large corporations, small family business, government institutions, and even normal individuals. The appearance of the modern bankruptcy law of the United States is signaled by the enactment of the Bankruptcy Reform Act in 1978 which, together with later amendments, constitute the current Bankruptcy Code of the United States; but also help them strategically restructure their financial or business affairs. However, the true world is never a vacuum. Among massive bankruptcy filings, there are a certain number of debtors who intend to simply eliminate or get rid of their obligations owing to creditors by way of discharge or to manipulate the bankruptcy system to frustrate creditors' efforts which are made to ensure or protect their own interests. Some commentators believe there should be some moral justifications for debtors' financial relief from bankruptcy, which can help restraint and regulate their conduct in the whole bankruptcy process. Good faith is regarded as one of such justifications. This thesis will discuss good faith in the legal context, especially dealing with the above-mentioned phenomenon regarding the debtors' good faith in US bankruptcy proceedings.