The invention discloses a supercritical carbon dioxide heat pump air pipe adjuster, which comprises a support frame. The support frame comprises a top frame and a bottom frame arranged oppositely; a transmission mechanism is arranged and fixed onto the bottom frame and is connected with an adjusting plate; an air pipe starting end clamping slot is formed in an end face of the adjusting plate; oneend of a heat pump air pipe is clamped and fixed into the air pipe starting end clamping slot; a driven wheel is fixedly arranged on one side of a surface of the top frame; a limiting frame is perpendicularly fixed to the middle part of the surface; a second sleeve pipe is fixed to a side wall of the limiting frame; a second fixing shaft is arranged and fixed to one end of the second sleeve pipe;a pressing seat and a driving wheel are fixed onto the second fixing shaft in a sleeving way; a handle is fixed onto the pressing seat; and the pressing seat, the handle and an elastic positioning seat are connected in a pressing way. According to the supercritical carbon dioxide heat pump air pipe adjuster provided by the invention, through the matching of the handle of the elastic positioning seat, a gasp between an annular slot of the driving wheel and an arc-shaped groove of the elastic positioning seat is changed, so that air pipes with different diameters are limited and fixed, and the supercritical carbon dioxide heat pump air pipe adjuster is wide in application range, and practicable to the air pipes with any size.