The invention relates to a nonquaternary oxime compound containing a quinoline parent nucleus as shown in a formula (I), and pharmaceutically-acceptable salt, isomer, prodrug and pharmaceutical composition thereof. The nonquaternary oxime compound can react with poisoned acetylcholin esterase in order to relieve a P-O covalent bond and reactivate the acetylcholin esterase. In the formula (I), R represents an oxime compound of benzene, imidazole, thiophene or substituted pyridyl, and the like. The invention further discloses a preparation method of the compound, and application of the compoundas a medicament, in particular to the application of the compound as a detoxifying medicament for treating organophosphorus pesticide poisoning. The formula (I) is shown in the description.