Abstract: To improve the comparability of the research results in ecological industry, the ecological footprint(EF) method was applied to analyze the resources utilization and environmental pollution among various sub systems of industrial process, taking maize-monosodium glutamate(MSG) industry as a case. The production of MSG is made up of three subsystems which are those of maize, starch, and MSG. Results indicate that the production process from maize to MSG is a prolonging process of the EF, in which the maize production occupied the biggest area, because its proportion of the EF of farmland and water resources is very high. It was found that the prolonging of EF follows the increase of resources profit, meaning that the prolonging of production chain is of importance to improve resources utilization efficiency. Authors augure that all three sub-systems have high proportion of the indirect energy EF, and reducing their energy consumption should become their targets sub-systems in which the air and water pollution in MSG subsystem is the most serious. Finally, it is considered that EF is a good method to measure resources utilization and environmental pollution in various subsystems of a integrated ecological industry.