Abstract: Automatic color measurement and control is a key technology of offset printing machines.It can improve the efficiency and quality of printing well.On the basis of the analysis of traditional color measurement and control method,the workflow,construction,and structure of the automatic color measurement and control system are determined.The key part of the system,including measurement system and control system are discussed in detail.The measurement system consists of densitometers,technique database and ink to color conversion algorithm module.And the control system consists of Direct Digital Control(DDC) system,ink key integrated control module,and ink key control panel.The JDF specification based automatic color measurement and control system workflow is established.Through the test and application to one domestic offset printing machine,the efficiency of the system is validated.