The present invention discloses an offline control circuit of an LED driver, which comprises a switching circuit, a voltagedivider, a voltage-feedback circuit, a current-feedback circuit and a cushionThe present invention discloses an offline control circuit of an LED driver, which comprises a switching circuit, a voltagedivider, a voltage-feedback circuit, a current-feedback circuit and a cushioncircuit. The switching circuit generates a plurality of LED currents through a transformer. The voltage-feedback circuit generates a voltage loop signal in response to the voltage across the LEDs. Th circuit. The switching circuit generates a plurality of LED currents through a transformer. The voltage-feedback circuit generates a voltage loop signal in response to the voltage across the LEDs. The current-feedback circuit senses a plurality of LED currents for generating a current loop signal in response the maximum current of the LEDs. A buffer circuit generates a feedback signal in accordane current-feedback circuit senses a plurality of LED currents for generating a current loop signal in response the maximum current of the LEDs. A buffer circuit generates a feedback signal in accordance with the voltage loop signal and the current loop signal. The feedback signal is coupled to the switching circuit through an optical-coupler for controlling the maximum voltage and the maximum currce with the voltage loop signal and the current loop signal. The feedback signal is coupled to the switching circuit through an optical-coupler for controlling the maximum voltage and the maximum current of the LEDs, and thereby the service life of the LED can be prolonged.ent of the LEDs, and thereby the service life of the LED can be prolonged.