The present invention relates to a processing method for a financial transaction system for preventing hacking, including a multi-layered safety locking function using biometrics. The purpose of the present invention is to provide a financial transaction system including a multi-layered safety locking function, capable of enabling a signal transmitted by a conversion device in a biometric unit to always differ for convenience and safety of a client, and the processing method for the same. According to the present invention, the processing method for a financial transaction system for preventing hacking comprises: a first fingerprint requesting step (S820) of requesting authentication using a fingerprint in a case that a client terminal connects online for a financial transaction； a first fingerprint input step (S830) of inputting a first fingerprint on a terminal using the financial transaction system by a user； a first fingerprint information transmitting step (S835) of transmitting the fingerprint data to an individual financial transaction intermediate server after the first fingerprint input step (S830)； a first fingerprint information determining step (S840) of determining whether the first fingerprint corresponds to the first fingerprint information registered in advance in the individual financial transaction intermediate server when the first fingerprint information transmitting step is performed； a first fingerprint authentication signal transmitting step (S850) of transmitting the coincidence to a bank (or a credit card company) intermediate server in a case that the first fingerprint information on both sides correspond in the first fingerprint information determining step； a second fingerprint information requesting step (S860) of requesting second fingerprint information to the terminal by the bank (or the credit card company) intermediate server receiving the authentication signal in the first fingerprint authentication signal transmitting step； a seco
