A pixel circuit and a driving method therefor, a display substrate, and a display apparatus. The pixel circuit includes a driving sub circuit, a data writing sub circuit, a first light-emitting control sub circuit, a first reset sub circuit, and a bias sub circuit; the first reset sub circuit is connected to a first node and configured to write a first reset voltage to the first node in response to a first reset control signal; and the bias sub circuit is connected to a second node and configured to write a reference voltage to the second node in response to a bias control signal, thereby turning on the driving sub circuit.