2,2-Dichlorocyclopropylmethyl-phosphoric acid derivatives of the formula I ##STR1## where R.sup.1, R.sup.2 and R.sup.3 are identical or different and are hydrogen or methyl,R.sup.4 is unbranched or branched alkoxy of up to 4 carbon atoms, unbranched or branched alkylthio of up to 4 carbon atoms, amino, or alkylamino or dialkylamino, where each alkyl is of up to 5 carbon atoms and is linear or branched,Y is oxygen or sulfur andX.sup.1, X.sup.2, X.sup.3 and X.sup.4 are identical or different and each is hydrogen, halogen, nitro, cyano, methyl or methylthio,and their use for controlling pests from the classes of insects, Arachnidae and Nemathelminthes.