A method of determining driving signals for a four-color organic electroluminescence device is provided. The driving signals are for displaying a predetermined color. A three-color organic electroluminescence device is a reference. The method comprises: a) defining a value of a white signal equal to the lowest value of a red reference signal, a green reference signal and a blue reference signal; b) defining a value of a red signal equal to the value difference between the red reference signal and the white signal, defining a value of a green signal equal to the value difference between the green reference signal and the white signal, defining a value of a blue signal equal to the value difference between the blue reference signal and the white signal; and c) adjusting the values of the red signal, the green signal or the blue signal for compensating color shifting.