A pest control composition comprises: [a] ester compound of formula (I), (wherein X represents hydrogen atom or cyan group, Z represents hydrogen atom or fluorine atom, and the R1 and R2 respectively represent hydrogen atom, optionally halogen atom substituted C1 - C3 alkyl or halogen atom) and ( b ) 2, 2-dimethyl-3- (1-allyl) cyclopropane carboxylic acid ( 2, 3, 5, 6- tetrafluoro-4-(methoxy methyl) phenyl) methyl ester, wherein the mass ratio of [a] to [b] is 50:1 to 1:50.
