In this paper the thermodynamic and reactivity study of light alcohol fuels was prepared, based on experimental and numerical results. We also tested the influence of water addition on fundamental properties of the combustion reactivity dynamics in closed vessels, like the maximum explosion pressure, maximum rate of pressure rise and the explosion delay time of alcohol-air mixtures. Substances that we investigated were: methanol, ethanol, n-propanol and iso-propanol. All experiments were conducted at initial conditions of 323.15 K and 1 bar in a 20 dm3 closed testing vessel. We investigated the reactivity and thermodynamic properties during the combustion of liquid fuel-air mixtures with equivalence ratios between 0.3-0.7 as well as some admixtures with water, to observe water mitigation effects. All light alcohols samples were prepared at the same initial conditions on a volumetric basis by mixing the pure components. The volumetric water content of the admixtures was varied from 10 to 60 vol%. The aim of water addition was to investigate the influence of thermodynamic properties of light alcohols and to find out to which extent a water addition may accomplish mitigation of combustion dynamics and thermodynamic reactivity.