Abstract: As an important tool in the studies of the mobility, division and fate of cells, the cell image technology is very useful under the condition of fluorescence. In order to achieve signal detection in weak light level, a cooling CCD image system for fluorescence cell observation is developed, complete with the design of structure and circuits, which consists of CCD chips used for medical imaging, CCD drive circuit based on FPGA and cooling device with TEC. By analyzing the characteristics of modules, an efficient cooling structure is designed, to improve the quality of image.