The miniaturization of spectrometer is helpful to increase its application. An optical layout was designed for a miniature CCD spectrometer for visible light. The proper optical fiber, plane directional optical grating and concave reflector were chosen and integrated together based on the theoretical computation for the optical layout of the spectrometer. The entrance light was dispersed and directly projected onto the active area of a CCD by focusing reflection and beam splitting. The optical layout was greatly simplified and the size of the spectrometer was reduced. Compared with other products, it is more accurate.