The invention discloses a portable air conditioner mounting support, and relates to the field of air conditioners. The portable air conditioner mounting support comprises an outdoor unit support, an indoor unit support and an adjusting plate; the two sides of the adjusting plate are provided with a first moving track and a second moving track respectively, and the first moving track and the secondmoving track are parallel to each other; and the outdoor unit support and the indoor unit support are movably connected with the first moving track and the second moving track respectively. The portable air conditioner mounting support has the advantages that an integrated structure is adopted, so that disassembly and assembly of an air conditioner are facilitated, and the movable function of theportable air conditioner is reserved; and the distance between the outdoor unit support and the indoor unit support can be adjusted according to the thickness of a wall body, and the portable air conditioner mounting support is suitable for being installed on a plurality of windowsills.