The present invention relates to malononitrile compounds of formula (Y):
##STR00001## wherein R.sup.1 and R.sup.2 are the same or different and
independently C.sub.1-C.sub.5 (halo)alkyl, C.sub.1-C.sub.5
(halo)alkyloxy, C.sub.2-C.sub.5 (halo)alkenyl, C.sub.2-C.sub.5
(halo)alkynyl, hydrogen, or cyano; R.sup.3 is C.sub.1-C.sub.3 haloalkyl,
C.sub.2-C.sub.4 haloalkenyl, or C.sub.2-C.sub.4 haloalkynyl; m is an
integer of 1 to 3; R.sup.5 is halogen, cyano, nitro, C.sub.1-C.sub.4
(halo)alkyl, or the like; n is an integer of 0 to 4, with the proviso
that when n is 2 or more, then R.sup.5's are the same or different from
each other; R.sup.6 is hydrogen, halogen, cyano, nitro, C.sub.1-C.sub.4
(halo)alkyl, or the like; as well as pesticide compositions containing
these compounds as active ingredients. The present invention makes it
possible to effectively control pests such as insect pests, acarine
pests, and nematode pests.