There is provided a novel pest control agent, particularly an insecticide or miticide. A substituted isoxazoline compound of General Formula (1):where A1, A2 and A3 independently are CH or N, etc., X1, X2 and X3 are independently are H, a halogen atom, etc., Y1 is H, etc., R1 is —C(O)R1a, —C(S)R1a, R1a is —C(R9)(R9a)—S(O)rR10, —C(R9)(R9a)—S(O)t(R10)═NR11, etc., R2 is H, etc., R3 is CF3, CClF2, etc., R4 is H, etc., R9 is H, etc., R9a is H, etc., R10 is C1-2 alkyl, etc., R11 is H, etc., r is an integer of 0-2, t is an integer of 0 or 1 and a pest control agent comprising the compound or the salt thereof.
