Biosurfactants can be defined as the surface-active biomolecules produced by microorganisms with wide-range of applications. In recent years, due to their unique properties like specificity, low toxicity and relative ease of preparation, these surface-active biomolecules have attracted wide interest. Due to their unique functional properties, biosurfactants were used in several industries including organic chemicals, petroleum, petrochemicals, mining, metallurgy (mainly bioleaching), agrochemicals, fertilizers, foods, beverages, cosmetics, pharmaceuticals and many others. They can be used as emulsifiers as well as demulsifiers, wetting agents, foaming agents, spreading agents, functional food ingredients and detergents. The interfacial surface tension reducing ability of biosurfactants made them to play important role in oil recovery and bioremediation of heavy crude oil.The three major functions played by biosurfactants. They were used to increase the surface area of hydrophobic substrates. Biosurfactants also used to increase the bioavailability of hydrophobic substrates through solubilization/desorption. They also regulate the attachment and removal of microorganisms from the surfaces.Biosurfactants possess both hydrophilic and hydrophobic regions causing them to aggregate at interfaces between fluids with different polarities such as hydrocarbons and water hence, decrease interfacial surface tension. They also found to be enhancing the nutrient transport across membranes and affect in various host-microbe interactions.