Provided are a breaker mechanical characteristic performance testing method and system. The breaker mechanical characteristic performance testing method includes that the standard characteristic quantity values with the reserved groups located on the same two-dimensional plane coordinate with characteristic quantity waveforms are selected by collecting the characteristic quantity waveforms of the mechanical characteristics in the breaker acting process, the distance between the characteristic quantity values in the characteristic quantity waveforms matched with the standard characteristic quantity values and the standard characteristic quantity values is calculated, and the offset distance of the characteristic quantity values is determined; and the distance between the standard characteristic quantity values and the original point of the two-dimensional plane coordinate is calculated, and the normalized offset distance is determined by dividing the offset distance of the characteristic quantity values by the distance between the standard characteristic quantity values and the original point of the two-dimensional plane coordinate. Users can obtain the values of the offset degree and the similarity of the characteristic quantity values according to calculation, and thereby evaluating the breaker mechanical performance and forecasting potential fault hidden dangers of the breaker mechanical performance. In addition, the breaker characteristic quantity value deterioration degree can be evaluated in real time according to the calculated offset distance of the characteristic quantity values.