The aroma and fragrance industry is billion dollar world market which grows at the rate of 18 billion per year and the essential oil in International trade increases 10% annually.In both developing and developed countries the requirement of aromatic plants containing essential oil has risen exponentially and it is expected that in future the demand of essential oil could be raised. Plant growth and their primary and secondary metabolite production is control by the plant growth regulators Plant growth regulators result the effects on plant like plant growth,number of essential oil storage structures and biosynthesis of essential oil which can alter the yield of essential oil. Phytohormones play significant role in enhancing the essential oil production. In most of the aromatic plants such as rose scented geranium, lemongrass, peppermint the quality and content of essential oil can be enhanced by the application of plant growth regulator.