The present disclosure provides a pixel driving circuit, a driving method thereof, and a layout structure of a transistor. The pixel driving circuit includes a storage capacitor, a first to a seventh switching transistor, a first driving transistor, a second driving transistor, and an organic light emitting diode. The layout structure includes a circuit node and an active layer connected to the circuit node; the active layer includes: a first active layer, a second active layer, and a third active layer; a first source, a drain and a second source connected to the first, the second and the third active layer, respectively; a first gate, a second gate, and a third gate corresponding to the first, the second, and the third active layer respectively; and a gate pattern composed of the first gate, the second gate, and the third gate being located above the circuit node and the active layer.