The esterification of tri-ethylene glycol with methacrylic acid under identical conditions of catalyst concentration, for synthesis of tri-ethylene glycol di-methacrylate using sulphuric acid and methane sulphonic acid as catalyst is discussed. The reaction by-products are lesser in case of methane sulphonic acid catalyst, in comparison to sulphuric,acid catalyst. Therefore the yield of ester product, tri-ethylene glycol di-methacrylate achieved during the synthesis is higher with the use of methane sulphonic acid as a catalyst, than on use of sulphuric acid as catalyst. This concludes that methane sulphonic acid has better catalyst selectivity in comparison to sulphuric acid for the synthesis of tri-ethylene glycol dimethacrylate. Methane sulphonic acid when neutralized is easily bio-degradable which is also desirable from environmental point of view.