The present invention relates to a loosening mechanism and an aerial fog generating device, wherein the loosening mechanism comprises a rotating portion; the rotating portion comprises an outer housing and an inner housing, the outer housing is sleeved onto the inner housing, and the inner housing is used for placing an aerial fog forming substrate; a pressing mechanism is provided on the inner housing, the outer housing is capable of moving along a circumferential direction, and the circumferential movement is converted into axial movement to drive the pressing mechanism to apply a radial pressing force to the aerial fog forming substrate; the inner housing is capable of being rotatably connected to the aerial fog generating device between a first position and a second position, and the aerial fog forming substrate and a heating element are capable of generating relative movement in the circumferential direction in the process from the first position to the second position; and the aerial fog forming substrate is in contact with the heating element in the first position and the second position. By using the loosening mechanism, a user can easily pull out the aerial fog forming substrate from the heating element, so that the user can conveniently clean the aerial fog generation device.