The invention belongs to the field of elastic carbon materials, and discloses compressible composite carbon aerogel with high sensitivity and a wide linear sensing range as well as preparation and application of same. The method comprises the following steps: 1) dispersing MXene nanosheets in water to obtain an MXene suspension liquid; 2) uniformly mixing a water-soluble trivalent iron salt, an acid, the MXene suspension liquid and chitosan, freezing and drying the mixture to obtain a composite aerogel; 3) carrying out heat treatment on the composite aerogel in an inert atmosphere to obtain the composite carbon aerogel, the heat treatment refers to heating the components to 500-1200 DEG C and carrying out heat preservation for 0-12 hours. The method is simple and environment-friendly. Theprepared carbon aerogel has the advantages of high compressibility, high rebound resilience, excellent cycling stability, ultrahigh sensitivity and wide-range linear sensing, and is applied to a sensing device.