The invention discloses a firmware upgrading system based on communication interfaces and belongs to the technical field of electrons. A circuit structure comprises a communication interface module, a main controller module, a memory medium module and a mandatory upgrading module, wherein the main controller module comprises a main controller chip and a program firmware module. A user can obtain the latest firmware conveniently in real time, upgrade the system, timely eliminate various software bugs and acquire the latest functions during device operation, rights and interests of the user are guaranteed, simultaneously, operation in the upgrading process is convenient, and time of the user and a manufacture is not delayed due to upgrading of the firmware, so that the cost is saved. The program firmware module is composed of a guide module, an operation module and a backup module, can conduct upgrading and restoration of the firmware and provides a manual mandatory upgrading function, so that the real zero-risk upgrading is achieved.