After reviewing the basic idea, methods of optimization and scale up for fermentation process adopted by many researchers for quite a long time, the author believes that the static optimizing method based on the kinetic conception with conventional optimum operating condition, in fact, is only an extension of kinetic conception of chemical engineering to the fermentation process. Such being the case, the existence of cellular metabolic flux is often neglected. Thus, the viewpoint to emphasize the metabolic flux analysis and control in bioreactor is put forward in this paper. Through several further experiments, the optimization technology of fermentation process at multi-levels based on the parameter correlation methodology and scaling-up strategy with multi parameters modulation have been realized. With the development of process sensing and computer technology, the new concept bioreactor (FUS-50L(A)) is used for fermentation processes optimization and scale up. This new bioreactor aimed at the measurement of material flux has been successfully applied to the fermentation of penicillin, erythromycin, aureomycin, inosine, guanosine, as well as the cultivation of recombinant human serum albumin, malaria vaccine, etc. As a result, thirty percent to several folds increase in titers were achieved. The process can be directly used for the scale up of Permentor from 50 liters to several hundred liters, even to 100 m³.