Mutation signal processing methods, devices and medical detecting apparatuses are described. The method includes detecting whether or not a mutation signal exists in an input signal if the mutation signal exists in the input signal, processing the input signal by a filter to obtain an output signal, and updating a prestored difference value according to a difference value obtained by subtracting the output signal from the input signal and if the mutation signal does not exist in the input signal, using a difference value obtained by subtracting the prestored difference value from the input signal as the output signal.
