The invention discloses a prefabricated component of an assembly type regulating storage tank. The prefabricated component comprises corner units, front edge units, side edge units and middle units, the corner units comprise first longitudinal channels and first transverse channels, the middle of each first longitudinal channel is communicated with one end of the corresponding first transverse channel, one end of each first longitudinal channel is closed, the front edge units at least comprise second longitudinal channels and second transverse channels, and one end of each second transverse channel is communicated with the middle of the corresponding second longitudinal channel, the side edge units at least comprise third longitudinal channels and third transverse channels, the third transverse channels and the third longitudinal channels are communicated in an intersected manner, one end of each third longitudinal channel is closed, the middle units at least comprise fourth longitudinal channels and fourth transverse channels, and the fourth longitudinal channels and the fourth transverse channels are communicated in an intersected manner. According to the prefabricated component,the units can be spliced into storage regulating tank, a construction period can be shortened, factory programming prefabrication is achieved, and quality is controllable.