Nanoparticles are the materials characterised by dimensions of the order of 100 nm or less. They exhibit a high surface/volume ratio leading to different properties very different from those of the bulk materials. The development of uniform nanoparticles has been intensively pursued because of their technological and fundamental scientific importance. A number of chemical methods are available and are extensively used, but these are often energy intensive and use toxic chemicals. An alternative approach for the synthesis of uniform nanoparticles is the biological route that occurs at ambient temperature, pressure and at neutral pH. The main aim of this review is to enlist and compare various methods of synthesis of zinc-based nanoparticles with emphasis on the biological method.