A kind of the measurement technique of the dimension and the geometry error of large dimension workpiece with two light routes and two CCD sensors has been made. The mathematical models of the dimension and the geometry error based on the technology of CCD and laser are established. The application property parameter to measure workpiece dimension and geometry error and the design characteristic related supplemental hardware of CCD sensor are studied. An on-line data collection system based on laser and liner array CCD is developed. This systematic C8051 single-chip microcomputer as controler that adopt American CYGNAL company's production carry out handling and the collection of data. the system meets the measurement requirement of no-touch, on line and high precision with adopting of machine, laser and electricity comprehensive technology. The result can be got in this paper: the CCD sensor can meet the need of measuring dimension and geometry error of big workpiece and is no-touch, on line measurement and high precision. The on line collecting data system can achieve the expecting function, and measure data on line, and it also can easily connect with auto control apparatus.