Nowadays, IT has an important role in people's life. Bank is one of the example of institute which using IT in its daily tasks. Customer's personal information which has stored by the bank is considered as private and has to be saving securely by bank. Only legal staff of bank, also legal customers can operate any of the tasks. Hence, bank has own system to protect its transaction tasks such as online and offline transactions. Bank account hacking has caused millions money losses around the world. It is important to achieve how the security aspects in a banking system can influence great lost to the financial institution. This paper reports on the aiming at identifying and classifying Mobile banking payment security challenges. First, different security risks of mobile banking have been presented. In addition, different methods of encryption have been presented. Moreover, our method which has two layers of security has been presented. Furthermore, for preparing the security of the Network Layer, our method will authorize the Message format with Check sum.