The design and realization of the microcomputer System of multispectral digital camera based on single chip computer and CPLD had been introduced. Single chip computer was the core of the system,and a CPLD had been used to extend the control interface of it.The CPLD was programmed by VHDL and graphic editor,and made the CPLD a multiple-use I/O interface chip.The design not only predigested the circuit, minished the size of circuit board and reduced the power dissipation, but also was easy to modify the configure of interface.And it fit for applications of microcomputer system of the multispectral camera.