Surfactant micellization of Non-steroidal anti-inflammatory drugs (NSAIDs) such as Meloxicam carrying by surface active agent as polyethylene glycol sorbitan monostearate (Span 20) was determined by measuring the surface tension as a function of molar concentration in aqueous solution at different temperature ranged from 20°C to 50°C to investigate the critical micelle concentration (CMC). The values of the Gibbs surface excess concentration( Γmax ), minimum area occupied per molecule( Amin. ), surface pressure at CMC (Πcmc) was determined on basis of the standard Gibbs free energy of adsorption (ΔG°ads). The results indicated that CMC increased by temperature increasing for Span 20, and inversely for micelle of Meloxicam with Span 20. The thermodynamic parameters as standard Gibbs free energy(ΔG°), enthalpy(ΔH°), and the entropy(ΔS°) of drug-surfactant of micellization were evaluated using changing of CMC at different temperature. The results based on thermodynamic parameters investigated the spontaneously of micelle formation and that increase the possibility to predict the wettability of Meloxicam.