The invention discloses a bottom formwork pedestal for a beam lifting hole of a prefabricated beam pedestal, and relates to the field of prefabricated beam bases. The bottom formwork pedestal comprises a bottom formwork bent frame, a transferring structure and a supporting adjusting mechanism, wherein the bottom formwork bent frame is matched with the beam lifting hole in shape; the transferring structure comprises a plurality of rolling wheels arranged below the bottom formwork bent frame and rails allowing the rolling wheels to slide; and the supporting adjusting mechanism comprises a plurality of supporting beams and a plurality of supports, wherein the supporting beams are fixed to the lower portion of the bottom formwork bent frame, the supports are fixed to the lower portions of thesupporting beams, and the supports are used for adjusting the heights of the supporting beams. According to the bottom formwork pedestal, the bottom formwork bent frame can be stably supported at thebeam lifting hole, the bottom formwork bent frame can be in smooth connection with a plane of the prefabricated beam pedestal at the beam lifting hole, it is ensured that the beam forming alignment ofa poured prefabricated beam meets the reservation requirements, the bottom formwork bent frame can be quickly and conveniently disassembled and transferred out of the beam lifting hole so that the bottom-carrying lifting of the prefabricated beam can be conveniently completed.