Essential oils are highly concentrated substances extracted from flowers, leaves, stems, roots, seeds, barks, resins, or fruit rinds. These oils are often used for their flavor and their therapeutic or odoriferous properties, in a wide selection of products such as foods, medicines, and cosmetics. Extraction of essential oils is one of the most time and effort consuming processes. The way in which oils are extracted from plants is important because some processes use solvents that can destroy the therapeutic properties. There are wide number of ways to extract the Essential oil but the quality never remains the same. Here we are using the “Steam Distillation” method for extraction which is the cheapest way for the extraction of Oils from the different parts of the plants. In this process steam is allowed to pass through the extraction chamber which contains plant matter. When steam passes through the herb material under pressure which softens the cells and allows the essential oil to escape in vapor form. The vapour allows to pass through condenser and oil is collected in separating funnel and separated. Composition data for Eucalyptus oil were studied and found the Eucalyptus oil can be used as cosolvent which results in depression of cloud point temperature.