In this paper， the author put forward to the systematic view on portfolio technological innova tion and provided a systematic framework of firm innovation system ，by which most Chinese enterprises could use it to manage innovation process．At this system ，the author provides four subsystems of firm systems：entrepreneur，R＆D，education and government．Cases from high tech as well as traditional manufacturing firms are drawn to verify the hypothesis．The structure and framework for firm innovation systerm are also provided．