The present invention provides a system of sensing AMOLED pixel driving property and an AMOLED display device. In the sensing stage, the anode voltage of the organic light emitting diode and the output voltage of the variable negative voltage source (21) in the AMOLED pixel driving circuit (10) are coupled to the voltage addition circuit (22), and the voltage addition circuit (22) inputs the sum up result to the analog to digital converter (23), and because the variable negative voltage source (21) adjusts according to a change of the anode voltage of the organic light emitting diode, and the variable negative voltage source (21) and the voltage addition circuit (22) act together, and then an input voltage of the analog to digital converter (23) can be adjusted to make the input voltage always be in a sensing range of the analog to digital converter (23).