Commercial oils  of Pimpinella anisum  L., Eucalyptus globulus  L., Funiculum vulgare L. and  Cuminum cyminum  L. plants  were tested  at the concentration of 2.5 % on the 4^th instar larvae of Spodoptera littoralis.   Feeding larvae on treated leaves with  Pimpinella anisum  and Eucalyptus globulus significantly reduced larval weight gained. There were no significant differences on fresh food consumption between all commercial oils tested and control;  also between days  and  interaction between treatments and days. The results showed that all the tested commercial oils significantly reduced fresh weight of faeces. A 2.5 % concentration of Cuminum cyminum  oil  caused 50 % mortality,  while  the same concentration of Eucalyptus globulus  oil caused 64.3 % malformation of the resulting pupae.All commercial oils treatments significantly reduced fecundity and fertility.        Histobiological activity ofC. cyminum  and / or E. globulus   oil on the mid-gut of the treated  larvae resulted  in degreesof morphological abnormalities.