This paper studies the real-time acquisition method of machine tool processing data and analyses the collected data in different actual application scenarios in order to solve the general problem of insufficient utilization of CNC machine tools. The most widely used communication protocols, OPC UA and MTConnect, are discussed and used for machine tool information collection. With the help of data analysis algorithms, five machine tool status indicators are proposed to comprehensively evaluate machine tools and presented in the form of radar maps which is useful for users to quickly get the current status. These achievements are applied for the on-line monitoring system of machine tools, which improves the utilization of machine tools.