A pixel driving circuit comprises a storage capacitor, a transistor, a transfer circuit, a driving element, and a switch circuit. The storage capacitor comprises first and second nodes. The transistor has a gate coupled to a discharge signal and is coupled between the first and second nodes. The discharge signal turns on the transistor in first and second discharge periods to discharge the storage capacitor. The transfer circuit outputs a data signal or a reference signal to the first node of the storage capacitor. The switch circuit is coupled to the driving element, a first display element and a second display element. The switch circuit can make the driving element diode-connected in first and second data load periods, and allow a driving current through a first display element in a first light-emitting period and a second display element in a second light-emitting period.