The environmental pollution caused by rapid industrialization has augmented for several decades and there is a communal anticipation to design maintainable chemical processes so that fewer toxic materials are generated. Recently ionic liquids and its derived systems are projected as alternatives for traditional solvents because of their clean, effective and environment friendly nature. This class of solvents are tagged as ‘’designer solvents’’ due to their tunable nature and incomparable properties. The potential of ionic liquids has expanded in terms publications, so this review is devoted to a subclass of ionic liquids i.e., protic ionic liquids (PILs) with a special stress on their physicochemical properties like high thermal, electrochemical and ionic conductivity. Protic ionic liquids serve as perfect electrolytes and exhibit proton conductivity as well as activity in fuel cell electrode reactions. The good electrolytic behavior facilitates proton transport in non-aqueous condition which is one of the vital requirements in proton exchange membrane fuel cell. To exhibit better thermal stability the PIL based fuel cell electrolyte should have ΔpKa greater than 15 since the open circuit voltage displays maximum ΔpKa in the range of 16–18. PILs offer to be promising candidate for fuel cell applications and greatly enables the use of renewable energy sources.