The application discloses a pixel circuit based on a double-gate transistor and a drive method thereof. In one embodiment, the pixel circuit comprises a light-emitting device OLED, a drive transistor T1, switch transistors T2-T5, a capacitor C1 and a capacitor C2; and the drive transistor T1 is a double-gate transistor and is used to drive the light-emitting device OLED to emit light. For the drive transistor in the pixel circuit of the application, the double-gate transistor is used to replace a single-gate transistor as a drive transistor in a traditional technology, a bottom gate of the double-gate transistor is used as the main gate, and then a top gate source voltage is used to adjust a threshold voltage of the drive transistor; and, because stability of a double-gate a-IGZO TFT is higher than stability of a single-gate device, the double-gate a-IGZO TFT can achieve threshold extraction and compensation and can achieve good display uniformity at the same time.