Nano filtration is a technique that has succeeded in the course of recent years which is used most often with low total dissolved solids water such as surface water and fresh ground water. Divalent and larger ions are generally targeted to be removed by Nano filtration. Monovalent ions pass through Nano filtration membrane so it is widely used for desalting application. Removing hardness and dissolved organics from water, arsenic removal from drinking water, heavy metal ions recovery from electro plating waste water and separation of pharmaceuticals from fermentation broths are some of the examples of industrial applications of nano filtration. NF has properties that lie between Ultra filtration (UF) and Reverse Osmosis (RO) with pore size of 0.01-0.001 µm. Since all NF membranes have their origins in reverse osmosis (RO) membranes, they are called loose reverse osmosis membranes or tight ultra filtration membranes with respect to it’s permeate flux and separation performance.