Abstract: The invention discloses an indoor adaptive ventilation system and method based on multi-vent ventilation modules, comprising at least one multi-vent ventilation module, the multi-vent ventilation modules comprise air reversing valves and ventilation ducts, the multi-vent ventilation ducts are connected with the air reversing valves, the air reversing valve comprises a box body, a box cover, a reversing mechanism, a supply air main duct, a return air main duct, a fixed supply air branch duct and multiple variable air direction branch ducts; a plurality of variable air direction branch ducts are evenly arranged in the circumferential direction of the box body. The invention can divide the indoor space into different sub-spaces, control pollutants in a smaller area, reduce the possibility of large-scale pollutant diffusion, and realize that the supply air outlets and the return air outlets can be switched mutually to adapt to different usage scenarios and needs.