In this paper, the micellization of anionic surfactant sodium dodecyl sulphate (SDS) and cationic surfactant Ndodecylpyridinium chloride (DPC) in aqueous solution at various temperatures has been reported using conductivity measurements. The thermodynamic parameters of micellization; the free energy, ΔGmic0, the enthalpy, ΔHmic0, and the entropy, ΔSmic0 were calculated from the critical micelle concentration (CMC) at different temperatures. The results show that the CMC of surfactants decreases to reach a minimum and then increases with temperature. Also, the thermodynamic parameters of micellization are discussed.