With the changes of upstream runoff amount, there are many different opening modes of the release sluices of a hydro-junction within a hydrologic year, which cause different flow fields and affect the flow condition in the entrance area of the navigation lock. Therefore, we studied the research data on the opening modes of the release sluice, which are considered as the successful experience under different boundary conditions, so as to explore the rule and trend of the opening modes of sluice gates and propose some suggestions in principle.