Abstract: The main teaching content for chemical system engineering with the characteristic of complexity was classified into three major lines. Those major lines were three-transports and one-reaction (transport of quality, momentum and energy, chemical reaction), three-flows and one-state (flow of mass, energy and information, optimal state), and three-functions and one-efficiency (function of digital, information and intelligent, efficient). In teaching practice, the physical significance and the interrelation of three main lines were illustrated based on the level of molecule, equipment and process, which resulted in the satisfied teaching effects. Moreover, the good teaching effects proved that the reorganization of chemical system engineering had an important reference and a guiding significance for the teaching innovation of chemical system engineering.