The invention discloses a mobile phone-based loan system. With the system, a borrower can borrow money anytime and anywhere, and can borrow money and pay back freely within a given credit limit. The mobile phone-based loan system is installed on a network device which is composed of a mobile phone, a server, a third-party server and a bank server connected by a mobile communication network and the Internet. The mobile phone-based loan system comprises a Feidai mobile phone system APP, a load balance module, a mobile phone service module, an SMS service module, a face scanning module, a unified interface module, a fast calculation module, a check module, a clearing service module, a bank interface module, a third-party service module, and a bank terminal. Customers fill in loan application information via the Feidai mobile phone system APP so as to withdraw money or pay back. Compared with the prior art, with the mobile phone-based loan system, customers can borrow money or pay back on a mobile phone, operation is easy, there is no need to wait in line in a bank outlet, customers can borrow money quickly, there is no repayment deadline, and customers can borrow money and pay back freely within a given credit limit.