The rice leaffolder moth, Cnaphalocrocis medinalis, is widely distributed in humid tropical to temperate countries of Asia, Oceania, and Africa. It is an important leaf feeding pest of rice. It's known that one leaf folder consumes 6 to 7 leaves during larval stage. Recently, it has become widespread throughout the major rice growing regions of Asia and become serious pests. The synthetic sex pheromone may not only be an effective monitoring tool for timing insecticide application, but also a possible control agent. Previously, two compounds, (Z)-11-hexadecenyl acetate (1, Z11-16:Ac) and (Z)-13-octadecenyl acetate (6, Z13-18:Ac), were identified as the female sex pheromone of the rice leaffolder moth and field tested in India and Philippines (Figure 1). On the other hand, additional four compounds, (Z)-11octadecen-1-ol (2, Z11-18:OH), (Z)-11-octadecenal (3, Z-1118:Ald), (Z)-13-octadecen-1-ol (4, Z13-18:OH), and (Z)-13octadecenal (5, Z13-18:Ald) were identified in Japan. In order to control the pest eco-friendly the obtention of each pheromone component is essential. A new method is described for the stereospecific syntheses of six sex pheromone components 1 to 6 for the rice leaffolder moth. The crucial synthetic step for the compounds is the introduction of pure (Z)-double bond in the molecules. The starting material, cis-1,8-oct-4-en-diol (7) consisting of 100% (Z)configuration was stereospecifically prepared from readily available 1,5-cyclooctadiene by known synthetic method (Scheme 1). The diol 7 was monoprotected with dihydropyran (DHP) and then, tosylated to give compound 9. The Grignard reaction to the tosylate with methylmagnesium chloride or n-propylmagnesium chloride gave each coupling products 10 or 11 in high yields (Scheme 2). Continuously, deprotection and then, tosylation of the THP ethers produced the intermediates 14 and 15. On the other hand, bromides 16 and 17 were easily prepared from the corresponding diols by monobromination and