An OLED driving power source, comprising a power supply board connected with a mainboard and an OLED screen , wherein the power supply board comprises a power supply circuit , a first conversion module , a second conversion module and a switch ; after powering on, the power supply circuit starts the first conversion module according to an on-off signal output from the mainboard , the first conversion module outputs a first voltage and a second voltage to supply power to the mainboard , as well as outputs a high-voltage direct current (HVDC) to the second conversion module ; the switch converts the first voltage into a first enabling voltage before outputting to the OLED screen for power according to a first enabling signal output from the mainboard ; the power supply circuit controls the second conversion module to start according to a second enabling signal output from the mainboard , the second conversion module converts the high-voltage direct current into a second enabling voltage to supply power to and light up the OLED screen , the first conversion module comprises a PFC circuit and an auxiliary path LLC control circuit wherein the PFC circuit starts and outputs a high-voltage direct current to the auxiliary path LLC control circuit , the auxiliary path LLC control circuit converts the high-voltage direct current into the first voltage and the second voltage before outputting to the mainboard for power, and characterized in that the PFC circuit is a bridgeless PFC circuit, and the bridgeless PFC circuit and the auxiliary path LLC control circuit are integrated in a same semiconductor chip package; and wherein the power supply board further comprises a standby circuit , and after powering on, the standby circuit outputs supply voltage to the mainboard and the power supply circuit , wherein the standby circuit comprises a standby circuit controller and a third transformer, the standby circuit controller outputs supply power to power the mainboard and the power supply circuit through the third transformer. after powering on, the power supply circuit starts the first conversion module according to an on-off signal output from the mainboard , the first conversion module outputs a first voltage and a second voltage to supply power to the mainboard , as well as outputs a high-voltage direct current (HVDC) to the second conversion module ; the switch converts the first voltage into a first enabling voltage before outputting to the OLED screen for power according to a first enabling signal output from the mainboard ; the power supply circuit controls the second conversion module to start according to a second enabling signal output from the mainboard , the second conversion module converts the high-voltage direct current into a second enabling voltage to supply power to and light up the OLED screen , the first conversion module comprises a PFC circuit and an auxiliary path LLC control circuit wherein the PFC circuit starts and outputs a high-voltage direct current to the auxiliary path LLC control circuit , the auxiliary path LLC control circuit converts the high-voltage direct current into the first voltage and the second voltage before outputting to the mainboard for power, and characterized in that the PFC circuit is a bridgeless PFC circuit, and the bridgeless PFC circuit and the auxiliary path LLC control circuit are integrated in a same semiconductor chip package; and wherein the power supply board further comprises a standby circuit , and after powering on, the standby circuit outputs supply voltage to the mainboard and the power supply circuit , wherein the standby circuit comprises a standby circuit controller and a third transformer, the standby circuit controller outputs supply power to power the mainboard and the power supply circuit through the third transformer. <EOS>