A conductive，fire-retardant and superhydrophobic cotton fabric was prepared by the in-situ deposition of polydopamine，MXene and ionic liquid on the surface of cotton fabric and subsequent hydrolysis-condensation reaction between ethyl orthosilicate and hydroxyl silicone oil to form a low-surface-energy hybrid layer. The chemical structure，micromorphology，hydrophobicity and fire retardancy of the cotton fabric were studied. Piezoresistive pressure sensors were prepared by assembling electrodes on the cotton fabric，and the piezoresistive sensing properties as well as the application in human motion detection were investigated. The results showed that the water contact angle and sliding angle of the cotton fabric reached 154. 4° and 6. 7°，exhibiting excellent anti-adhesion and self-cleaning performances. The cotton fabric possessed good fire retardancy and could be quickly extinguished within 3 s after ignition. The cotton fabric-based piezoresistive pressure sensordisplayed high sensitivity，wide pressure detection range，fast response and excellent repeatability，and the signals were not affected by artificial sweat. The sensor had been successfully applied for human motion detection.