6-deoxy-6-thioether-amino acid cyclodextrin derivative is obtained by condensing an amino acid derivative with halogenated cyclodextrin in presence of alkali. The 6-deoxy-6-thioether-amino acid cyclodextrin derivative includes 6-deoxysulfinyl-6-thioether-amino acid cyclodextrin derivative and 6-deoxysulfonyl-6-thioether-amino acid cyclodextrin derivative. Compounds provided are for reversing neuromuscular relaxation in patients and animals induced by muscular relaxants. The compounds are able to rapidly reverse and antagonize muscular relaxation induced by muscular relaxants and can be administrated in preparing a drug having an antagonist effect on muscular relaxation. The compounds have low production cost and are able to reverse and antagonize a wide rage of muscular relaxations, thus effectively broaden scope of clinical use. More importantly, the compounds have a safe dose at least doubled compared to prior arts. The compounds have a general formula (I).