RESUMEN
Basil [Ocimum basilicum], a member of Lamiaceae family, is used in traditional Iranian medicine. Essential oils of basil leaves are composed of phenylpropanoids which are important in treatment of headaches, diarrhea, coughs, warts, worms and kidney malfunctions. The most important phenylpropanoid compounds contain eugenol, chavicol, methyl eugenol, methyl chavicol, myristicin, methyl cinnamat and elemicin. Biosynthesis of phenylpropanoids that passes from shikimate pathway, are regulated by an enzyme group. Phenylalanine amonia-lyase [PAL], cinnamate 4 - hydroxylase [C4H], 4 - coumarate CoA ligase [4CL], P- coumarate 3-hydroxilase [C3H] and O - methyltransferases [EOMT, CVOMT, COMT] are known as key enzymes regulating at production of phenylpropanoids. The phenylpropanoids are also produced in the area of stress conditions and maintained the plant against biotic and abiotic stresses. The purpose of this study is introducing Basil and its medicinal usages in Iran and an overview of the phenylpropanoid biosynthesis as an important part of the essence in basil and its evaluation of agronomic characteristics