A digital filtering system, method, and recording medium thereof are described. In the system, firstly a sensor obtains an analog physiological signal, a quantizing module transforms the physiological signal to a digitalized frequency domain signal, and then a specification parameter module obtains a feature model satisfying the frequency domain signal by matching, for a deciding process module to determine which decision parameter should be used. A filter-Clustering management module starts a relevant filter module according to the matching decision parameter to filter the frequency domain signal. On the contrary, when the frequency domain signal is an abnormal signal, the quantizing module outputs the abnormal signal to a back-end server system. The server system builds more than one updating parameter to update all the decision parameters and feature parameters. Therefore, the decision parameters and the feature parameters are updated on real time, and the physiological signal filtering result is quickly obtained.
