The invention discloses a dry-cleaning peel-off-type powder-residue-free decontaminating agent, and a preparation method thereof. The dry-cleaning peel-off-type powder-residue-free decontaminating agent comprises, by mass, 780 to 875 parts of a solvent, 30 to 45 parts of a decontamination auxiliary agent, 55 to 100 parts of an adsorbent, and 25 to 45 parts of a film forming agent. In applicationsof the dry-cleaning peel-off-type powder-residue-free decontaminating agent, the dry-cleaning peel-off-type powder-residue-free decontaminating agent is sprayed onto stain using an aerosol can, no powder is left after drying, a layer of thin film with toughness is formed, stain is degraded effectively and absorbed by the thin film; when the dry-cleaning peel-off-type powder-residue-free decontaminating agent on fabric stain is dried completely, the thin film can be removed through peeling off, no powder pollution is caused in decontamination process, no secondary residue is left, decontamination is quick, and treatment is convenient.