Novel 4-(3-butynyl)aminopyrimidine derivatives represented by general formula [I] are useful as pest control agents.In general formula [I], R is a mono- or bi-cyclic ring which may contains 0 to 3 heteroatoms, for example, phenyl or oxazolyl； R is a hydrogen atom, -R, -OR, -C(O)OR, -C(O)NHR, -CONR (wherein R is straight-chain or branched C alkyl, or the like), hydroxyalkyl, or the like； R is a hydrogen atom, a halogen atom, acyloxy represented by (straight-chain or branched C aliphatic hydrocarbon group)-CO-O-, or the like； and R is a hydrogen atom, a halogen atom, C alkyl, or the like, or alternatively, R and R together with the carbon atoms on the pyrimidine ring may form a thiphene ring, a pyrrole ring, an imidazole ring, a benzene ring, a pyrimidine ring, a furan ring, a pyrazine ring, or a pyrrolidine ring.
