The invention relates to a flyback converter which is provided with a self-driving synchronous rectifier. The invention utilizes a transistor as a second side rectifier to replace the traditional diode rectifier to lower the conduction loss. But the transistor is needed to be driven by a suitable gate driver. Traditionally, a force driving gate driver is adopted realized by an integrated circuit with being complex and expensive, and the circuit of an ordinary self-driving gate driver is still complex. The drive circuit of the flyback converter with the self-driving synchronous rectifier is formed that a second side drive coil is connected in series with a diode, a switch controller and a switch to manufacture the self-driving gate driver, wherein, the switch controller decides the openingor the closing of the switch. A current detecting circuit is utilized to be connected with the switch controller, and can detect current of the synchronous rectifier which is connected with a second side coil to control the switch controller. Thus, the flyback converter with the self-driving synchronous rectifier can efficiently simplify the complexity of the circuit and lower the cost.