The invention relates to a prefabricated reinforced concrete component with grooves and a manufacturing method thereof and belongs to the technical field of components in a prefabricated reinforced concrete structure. The component uses a cored slab prefabricated by reinforced concrete; and transverse grooves are arranged at the vertical edge of the reinforced concrete prefabricated slab at intervals, and are interacted with vertical holes parallel to the surface in the prefabricated slab. The manufacturing method provided by the invention comprises the following steps of: combining templates, such as a bottom die, a top die, a side die, a steel pipe inner die and the like on a production field of prefabricated slabs; arranging reinforcing meshes; then pouring concrete; drawing a steel pipe before hardening the concrete; and dismounting the templates after the concrete reaches to the expected strength. According to the prefabricated reinforced concrete component and the manufacturing method thereof provided by the invention, the industrial level of a building structure is improved, the load-carrying capability is improved, and resources can be saved. The prefabricated reinforced concrete component can be applied to various wall body bearing structures.