An organic light-emitting diode (OLED) pixel circuit, comprising: an OLED; a driving transistor, wherein a drain electrode of the driving transistor is connected to the OLED; a first switching unit, controlled by a scan line and configured to connect a data signal output end and a gate electrode of the driving transistor; a second switching unit, controlled by an emission line and configured to connect a power signal output end and a source electrode of the driving transistor; and a compensation circuit, connected to the gate electrode of the driving transistor and configured to maintain a voltage of the gate electrode of the driving transistor during a light-emitting period making use of an adjustable reference signal applied to the gate electrode of the driving transistor, so as to enable a current flowing through the OLED to be irrelevant to a threshold voltage Vth of the driving transistor, characterized in that the pixel circuit further comprises: a reference signal generation module, comprising a threshold voltage calculation module configured to either estimate based on usage time or measure the threshold voltage of the driving transistor, and configured to adjust, based on a current threshold voltage of the driving transistor calculated by the threshold voltage calculation module, the reference signal to be used by the compensation circuit, wherein a voltage of the reference signal and the threshold voltage meet at least one of validation conditions capable of validating the compensation circuit; and wherein the validation condition is such that the reference voltage is adjusted accordingly to the variation of the threshold voltage of the driving transistor. an OLED; a driving transistor, wherein a drain electrode of the driving transistor is connected to the OLED; a first switching unit, controlled by a scan line and configured to connect a data signal output end and a gate electrode of the driving transistor; a second switching unit, controlled by an emission line and configured to connect a power signal output end and a source electrode of the driving transistor; and a compensation circuit, connected to the gate electrode of the driving transistor and configured to maintain a voltage of the gate electrode of the driving transistor during a light-emitting period making use of an adjustable reference signal applied to the gate electrode of the driving transistor, so as to enable a current flowing through the OLED to be irrelevant to a threshold voltage Vth of the driving transistor, characterized in that the pixel circuit further comprises: a reference signal generation module, comprising a threshold voltage calculation module configured to either estimate based on usage time or measure the threshold voltage of the driving transistor, and configured to adjust, based on a current threshold voltage of the driving transistor calculated by the threshold voltage calculation module, the reference signal to be used by the compensation circuit, wherein a voltage of the reference signal and the threshold voltage meet at least one of validation conditions capable of validating the compensation circuit; and wherein the validation condition is such that the reference voltage is adjusted accordingly to the variation of the threshold voltage of the driving transistor. a reference signal generation module, comprising a threshold voltage calculation module configured to either estimate based on usage time or measure the threshold voltage of the driving transistor, and configured to adjust, based on a current threshold voltage of the driving transistor calculated by the threshold voltage calculation module, the reference signal to be used by the compensation circuit, wherein a voltage of the reference signal and the threshold voltage meet at least one of validation conditions capable of validating the compensation circuit; and wherein the validation condition is such that the reference voltage is adjusted accordingly to the variation of the threshold voltage of the driving transistor.