Essential oils and their derivatives are considered alternative means for controlling many harmful insects. As well, their rapid degradation in the environment and increased specificity do not harm beneficial insects. A method for the determination of Neem oil residues in eggplant (Solanum melongenaL.) by GC/Ms Mass is described. In this study, the effect of Neem essential oil (Azadirachta indica Juss) as biopesticide on the economical production of eggplant (Solanum melongena L.) was investigated.  Prior to use, the volatile and organic constituents of commercial applied Neem essential oil were identified using FTIR analysis.  After application, Azadirachtin is an active ingredient in neem oil which appears to cause 90% of the effect on most sucking pests. Among them, the major constituents are triterpenes known as limonoids, Nitrogen, Oxygen, Floride and Carbon atoms.
          Neem oil residues were detected in all samples from eggplant which were collected from the field after 12, 24 days of spraying. It appears that no effective material residue present.