Charging circuit capable of preventing current from flowing backwards

The invention discloses a charging circuit capable of preventing reverse current. The circuit comprises an electric quantity detection circuit, a triode circuit, a combined switch tube and a control module. The electric quantity detection circuit is connected with the input end of the control module and a battery needing to be charged. The electric quantity detection circuit outputs an electric quantity change value to the control module. The output end of the control module is connected with the input end of the triode circuit, the output end of the triode circuit is connected with the combined switch tube, and the combined switch tube is respectively connected with an external input power supply and a battery to be charged. The control module receives the electric quantity change value and outputs a battery abnormal signal, the triode circuit receives the battery abnormal signal, the triode circuit is not conducted, and the combined switch tube is converted from a closed state to an open state, so that the