An oxazepine compound, or salt thereof, has General Formula (I):wherein R1, R2, R3 and R4 may be identical or different, representing a hydrogen atom, halogen atom, alkyl group, etc. R5 and R6 may be identical or different, representing a hydrogen atom, alkyl group, or phenyl group, pyridyl group, etc., that may be substituted together with a carbon atom to which R5 or R6 is bonded R7 represents a hydrogen atom, alkyl group, alkynyl group, cyano alkyl group, alkoxy alkyl group, etc. Y represents an oxygen atom, S, NH, etc. Y1 represents a C═O, C═S, CH2 group, etc. A represents a CH group, etc. and m represents 0 or 1], as well as an agricultural/horticultural insecticide using such oxazepine compound or salt thereof as its active ingredient, and method for using the same.
