The invention discloses a building beam column reinforcement cage main reinforcement positioning frame. The building beam column reinforcement cage main reinforcement positioning frame comprises two top support steel beams which are arranged in parallel, a plurality of reinforcement cage bearing rods which are arranged at the tops of the two top support steel beams in parallel in the length direction of the top support steel beams and a plurality of support positioning mechanisms which are arranged at the bottoms of the two top support steel beams in parallel in the length direction of the topsupport steel beams, wherein one layer of main reinforcement of a reinforcement cage is erected on the reinforcement cage bearing rods, and a hooping is arranged outside the main reinforcement in a sleeving mode; and each support positioning mechanism comprises a bottom support rod and two vertical support parts which are oppositely arranged on the bottom support rod in the length direction of the bottom support rod. According to the building beam column reinforcement cage main reinforcement positioning frame, the first layer of the main reinforcement of the reinforcement cage and the hoopingarranged outside the first layer of the main reinforcement in the sleeving mode are horizontally supported by the reinforcement cage bearing rods, support seats are used for allowing positioning rodsupport parts to be placed, positioning rods are placed on two corresponding positioning rod support parts, the position of the main reinforcement is positioned through limiting by the positioning rods and the hooping, the positioning rod support parts are pulled out to enable the positioning rods to fall down, and taking out of the positioning rods is labor-saving.