The present disclosure provides a pixel circuit, its driving methods, an OLED display panel and a display device. The pixel circuit includes a driving controlling unit configured to, under the control of a first scanning signal and a second scanning signal, charge or discharge a first storage capacitor through a first level, a second level and a data voltage, so as to compensate for a threshold voltage of a driving transistor with a gate-to-source voltage of the driving transistor when an OLED is driven by the driving transistor to emit light; and a touch controlling unit including a touch sensor and configured to, under the control of the first scanning signal and the second scanning signal, sense by the touch sensor whether or not a touch is made and transmit a corresponding touch sensing signal to a touch signal reading line.