The invention provides a fixed support system for large-aperture air-conditioning standpipes in in super high-rise buildings. The fixed support system is used for supporting a plurality of air-conditioning standpipes which are arranged side by side in a tube well. The plurality of air-conditioning standpipes are divided into n groups, and n is greater than and equal to 2. The fixed support system comprises a plurality of layers of supports, wherein each layer of support is provided with a first main beam and a second main beam which are vertical and fixedly connected; the two main beams are respectively parallel to a first embedded iron anchor plate and a second embedded iron anchor plate which are embedded on a tube well wall surface, and one ends of the main beams are respectively and fixedly connected to the two embedded iron anchor plates; a secondary beam is arranged between at least one side of each standpipe and each standpipe; the two ends of the secondary beam are respectively and fixedly connected to the main beam and the embedded iron anchor plate parallel to the respective main beam; and fixed supporting seats which are in welding connection with the air-conditioning standpipes are respectively supported on the main beams and the secondary beams, surrounding the air-conditioning standpipes, of each group of supports. The fixed support system has the beneficial effects that the safe support of the large-aperture air-conditioning standpipes in limited tube well space is realized on the premise of ensuring the normal operation of the standpipes and the enough strength of the supports.