This article analyzes and makes critical comments on the supreme court cases in 2012 concerning Bill of Exchange, Note and Checks. But I selected the two representative cases. The representative cases are introduced in this article as following: Ⅰ. Introduction Ⅱ. 〔Supreme Court Case 2012da60015〕 1. The fundamental notions of the accommodation bill. 2. Acquisition of the accommodation bill without compensation relationship. Ⅲ. 〔Supreme Court Case 2010da106290〕 1. Effect and formula on the negotiation of an overdue bill (1) Effect on the negotiation of an overdue bill (2) Formula on the negotiation of an overdue bill 2. Defense for reasons of accommodation bill (1) The fundamental notions of the defense for reasons of accommodation bill (2) Violation of the counsel drawing an accommodation bill, and defense for reasons of knowingly to the detriment of the debtor (3) Defense for reasons of knowingly to the detriment of the debtor and shelter rule Ⅳ. Conclusion.