Abstract: An on-line vibration detected and intelligent control apparatus for cutting process which integrated with machine tool's I/O module and a method thereof are disclosed, which can detect vibration of the machine tool during a machining process and calculate a gain, which can be a plus value or a minus value, according to the detected vibration signal. By adding the gain to the current spindle speed or the current feed rate of the machining process, an updated spindle speed or an updated feed rate is obtained so as to be used in the machining process for compensating and thus preventing the vibration of the machine tool during the machining process.