Abstract: Metallurgical process engineering proposed by academician Ruiyu Yin is a new branch in the field of metallurgy, which deals with the physical nature, structure, and global behavior of metallurgical manufacturing process. Process interface technology used in steelmaking-continuous casting section (SCCS) is developed from metallurgical process engineering. It is used to study and analyze the running dynamics of mass flow in steelmaking plants. In recent years, the intelligent and green production in steelmaking plants has become the demand and necessity of the time because of the rapid development of intelligent manufacturing represented by Industry 4.0 in Germany. Nowadays, the automation control of single-process has been realized in most steelmaking plants at home and abroad, which is a stepping zone and has created the foundation for the intelligent and green production. But at the same time, importance also should be given for the improvement in the multi-process operation of SCCS considering the global optimization on steelmaking production. Undoubtedly the process interface technology is an important method to deal with the collaboration-optimization of process relationship set, but also it has a greater influence on the analysis-optimization of process function set and the reconstruction-optimization of process set. Therefore, the process interface technology has created lot of interest and drawn greater attention from scholars and experts of metallurgy, which results in the great improvement of the multi-process operation in SCCS. Currently, three kinds of classic process interface technologies, including ladle cycling control, crane running control, and operation mode optimization, have become the most important research areas because of their significant effect on the high-efficient connection of mass flow among multi-process. The scope of ladle cycling control includes the monitoring of thermal state and the matching and scheduling of ladles. The task assignment and multi-crane collaborative scheduling are the most important components of crane running control and it is of great interest to research further. When operation mode optimization is considered, the improvement of furnace-caster coordinating mode based on the matching of capacity and rhythm can be regarded as the most interesting research area. It is known that the operation mode is the fundamental for ladle cycling and crane running, and moreover, the status of ladle cycling and crane running also can guide the further optimization of operation mode. Based on above analysis, this paper presented a detailed overview of progress made in the research on abovementioned three kinds of classic process interface technologies in SCCS. Further, the necessity of collaboration between process interface technologies was also illustrated, aiming at unfavorable restraints of multi-process collaborative operation. In addition, the collaboration mechanisms and schemes of all three kinds of classic process interface technologies were described in detail. Finally, it is expected that this review could offer some reference and guidance for the improvements in multi-process operation of SCCS.