Pixel circuit, driving method therefor, and display device

Provided is a pixel circuit. The pixel circuit comprises a driving transistor (T1) and a light-emitting element (OLED) both connected in series between a first level end (VDD) and a second level end (VSS), and comprises a second transistor (T2), a third transistor (T3), a fourth transistor (T4), a first capacitor (C1) and a second capacitor (C2). The second capacitor (C2) is connected between a control pole of the driving transistor (T1) and a second end of the light-emitting element (OLED). A threshold voltage is stored by the first capacitor (C1), so that threshold voltage compensation for the driving transistor and the light-emitting element is implemented, and therefore the nonuniformity of the display of the pixel circuit is compensated. Also provided is a display device, wherein a first control line (CM) and a light-emitting control line (EM) are both global lines. Also disclosed is a pixel circuit driving method.