The present disclosure provides a pixel circuit, a driving method thereof, an array substrate and a display device. The pixel circuit comprises: a driving transistor; a precharge sub-circuit configured to write a supply voltage into a first node under the control of a scan signal and a light emission control signal in a precharge phase; a reset sub-circuit; a data writing sub-circuit configured to write a data voltage into the first node under the control of the scan signal in a data writing phase, so that the potential of the first node is equal to a sum of the data voltage and a threshold voltage of the driving transistor; a light emission control sub-circuit configured to connect a power supply with a light-emitting unit through the driving transistor under the control of the light emission control signal in a light-emitting phase.