A power supply circuit of a power amplifier, comprising a direct current/direct current converter chip, wherein the direct current/direct current converter chip comprises: an input pin; an inductance pin; and a feedback pin; wherein the input pin is connected to a power supply (V IN) and the inductance pin is connected to a voltage input end of the power amplifier through an LC storage circuit; wherein a control circuit is connected between the voltage input end of the power amplifier and the feedback pin; and the control circuit is configured to receive a control voltage (Vc) and adjust, through the control voltage (Vc), a voltage (V OUT) at the voltage input end of the power amplifier, and wherein the control voltage (Vc) is variable; wherein the power amplifier has at least two operating frequencies and has at least two power levels under each one of the at least two operating frequencies; wherein a corresponding relationship exists between the control voltage (Vc), the at least two power levels of the power amplifier and the at least two operating frequencies of the power amplifier, the control voltage (Vc) changes according to a change of power level of the power amplifier and changes according to a change of operating frequency of the power amplifier; wherein the control voltage (Vc) is corresponding to a minimum of the voltage (VOUT) at the voltage input end of the power amplifier enabling the power amplifier to work in a corresponding power level of the at least two power levels of the power amplifier and a corresponding operating frequency of the at least two operating frequencies of the power amplifier and satisfy a radio frequency index of a termina comprising the power amplifier; wherein the corresponding relationship is stored in a storage chip of the terminal. an input pin; an inductance pin; and a feedback pin; wherein the input pin is connected to a power supply (V IN) and the inductance pin is connected to a voltage input end of the power amplifier through an LC storage circuit; wherein a control circuit is connected between the voltage input end of the power amplifier and the feedback pin; and the control circuit is configured to receive a control voltage (Vc) and adjust, through the control voltage (Vc), a voltage (V OUT) at the voltage input end of the power amplifier, and wherein the control voltage (Vc) is variable; wherein the power amplifier has at least two operating frequencies and has at least two power levels under each one of the at least two operating frequencies; wherein a corresponding relationship exists between the control voltage (Vc), the at least two power levels of the power amplifier and the at least two operating frequencies of the power amplifier, the control voltage (Vc) changes according to a change of power level of the power amplifier and changes according to a change of operating frequency of the power amplifier; wherein the control voltage (Vc) is corresponding to a minimum of the voltage (VOUT) at the voltage input end of the power amplifier enabling the power amplifier to work in a corresponding power level of the at least two power levels of the power amplifier and a corresponding operating frequency of the at least two operating frequencies of the power amplifier and satisfy a radio frequency index of a termina comprising the power amplifier; wherein the corresponding relationship is stored in a storage chip of the terminal.