Background: Dengue fever is an acute febrile infectious disease in subtropical and tropical areas transmitted by Aedes aegypti mosquitoes. Early prediction of severity helps in reducing complications and mortality. Objectives: To determine the prognostic efficacy of biochemical markers i.e. S. lactate and LDH in predicting severity of dengue. Methodology: Tertiary hospital based observational test study during Dec 2015 to May 2017 where 150 patients above 18 years of age with Dengue fever were included. Results: As per severity of Dengue, two third of the cases (66.7%) were of dengue fever while 27.3% and 6% were of dengue hemorrhagic fever and dengue shock syndrome (severe dengue) respectively.