The invention relates to a surface desorption sampling method and a surface desorption sampling device by using plasma produced by dielectric barrier discharge. The device comprises an alternating-current high-voltage power supply, a high-voltage electrode, a ground electrode, an insulating medium, a discharge gas inlet and outlet, a cavity and the like. Certain alternating voltage is applied between the high-voltage electrode and the ground electrode, discharge gas is broken down to produce a large number of high-energy high-concentration electrons, ions and other species, the high-energy species pass through small holes on the ground electrode under the accelerating action of an electric field and bombard the surface of an object, and sample molecules to be detected such as explosive substances, poisonous substances and the like adsorbed on the surface of the object are desorbed from the surface of the object and enter analytical instruments of a mass spectrum, a mobility spectrum and the like through a gas carrier tape so as to be detected. By the method, in-situ on-line sampling can be realized, sampling efficiency is improved, and sampling time is shortened.