Theories of CCD and correlated double sampling are introduced, and a data acquisition system based on CPLD and CCD is designed. Driving timing sequences of CCD and AD9844 are produced by CPLD. The output signal of CCD is correlated double sampled by AD9844, then the analog signal is converted to the digital signals. Simultaneity, CPLD stores the data in the exterior RAM. Finally, MPU is used to complete the communication with computer, then the data is transmitted to computer. The system executes high speed data acquisition, data storage and processing. The result indicates that the circuit is characterized by simple framework, low cost and free modification of program. It will be of application value in the field of spectrum analysis.