Achieving Maslahah is one of the sharia objectives. The lack of clear evidence from Alquran and Al-sunnah concerning financial transaction makes its role very important. This paper aims to explain the concept of Maslahah and opinion of scholars of Maslahah as one of Islamic sources and their evidences. This paper also mentions legal maxim that has strong relationship with Maslahah. It also explains some of the application of Maslahah in Financial Transaction. The methodology of this paper is through qualitative research based on relevant literatures on Maslahah. The general finding of this paper shows that there are three categories of Maslahah in the application of financial transaction

Trading is one of the economic activities that is always carried out by the community. Trading is considered to be valid if it meets the terms and pillars in Islamic law. The goods must be determined in accordance with the general provisions, so that if there is a shortage or excess of the goods, the goods must be notified to the transacting party, this is intended to guarantee and provide protection to the consumer. Plastic bag is a very effective and inexpensive storage container for consumer items. In shopping activities, sometimes these plastic bags are provided free of charge and there is no sale and purchase agreement in the transaction. The phenomenon that occurs in some X franchise retailers in Ponorogo is to give discounts on plastic bags that are not purchased by consumers, while retailers include them in the list of groceries and the plastic bags are discounted at the time of payment. This type of research uses a qualitative approach and research field as research type with observation techniques, interviews, and documentation. Researchers conducted this study to know the Islamic law perspective on the practice of discounting plastic bags that are not purchased by consumers. The results of research on the practice of price reduction on plastic bags provided by franchise grocery stores is not meet the terms and pillars of transaction. Meanwhile, the price deduction in the Islamic law is basically allowed if it meets the terms and pillars for the transaction