Abstract: The stability of 6 pyrethriods was studied by GC/MS. The stability of 6 pyrethriods in methanol solvent and in apple juice concentrate under for 5 months was investigate. The stability in methanol solvent and in apple juice concentrate of 6 pyrethriods in rome temperature was also investigate. The result shows that the 6 pyrethriods is more stable in apple juice concentrate than in methanol solvent.