Disclosed are 5-(vinylamino)pyryazole derivatives of formula I or pesticidally acceptable salts thereof (I) wherein, for example, W is .dbd.N--, .dbd.CH--, .dbd.CR.sup.6-- or .dbd.C(NH2)-, R.sup.6 is halogen or haloalkyl, R.sup.1 is cyano, halogen, alkyl, haloalkyl or --CS--NH2, R.sup.2 is alkyl or cycloalkyl, R.sup.3 is alkyl, alkenyl, alkynyl, cycloalkyl, aryl, heterocyclyl, aralkyl, heterocyclylalkyl, --CO--O--R.sup.9, --CO--R.sup.10, --SO--R'', --SO.sub.2--R.sup.12; R.sup.9, R.sup.10, R.sup.11 and R.sup.12 are for example organic groups, R.sup.4 is halogen or --NH.sub.2, R.sup.5 is haloalkyl, haloalkoxy, halogen or --SF.sub.5, and n is an integer selected from 0, 1 or 2. These compounds cab be used for controlling pests, especially by treatment of domestic animals. ##STR00001##