Abstract: A method for filtering a vibration signal of a machine includes generating a control signal by a controller to control an operation process of the machine, sensing a vibration of the machine by a sensor in the operation process to output a sensing signal, reading the control signal and the sensing signal by a signal generating unit to generate a vibration signal concerned with the vibration according to the sensing signal, generating a filtering bench-mark point by a searching unit according to the control signal to gather characteristic signals and filtering vibration signals in a database by the searching unit according to the filtering bench-mark point, and filtering the vibration signal by a filtering unit according to characteristic signals and filtering vibration signals to generate a filtered vibration signal.