An oil-in-water (O/W) microemulsion was prepared by mixing palm-based methyl esters (PME) with water at a 25:75 by weight ratio. The microemulsion was stabilised with C_12-14 fatty alcohol ethoxylates (FAE) with 7 and 2 moles of ethylene oxide (EO), and palm-methyl ester sulphonate (MES) as mixed surfactants, and glycerol-derived co-surfactant (GTBE) and conventional 1,2-hexanediol as the cosurfactants. The mixtures were agitated vigorously and then stored at ambient temperature and 45^oC. Phase behaviour of the ternary-phase systems was periodically observed using the polarised light sheets. The ternary phase diagrams were then mapped. The physical characterisations of any stable microemulsions, such as the conductivity and viscosity solutions were also determined. The optimum concentrations of mixed surfactants (MES/ FAE 7/ FAE 2) and GTBE to form stable microemulsions were 20% (w/w) and 10% (w/w), respectively. A larger microemulsion region was also obtained for other system consisting of mixed surfactants (FAE 7/ FAE 2) and GTBE with the optimum concentrations of mixed surfactants and co-surfactant for producing full microemulsions were 15% (w/w) and 10% (w/w), respectively. Physical characterisations of the stable microemulsion solutions showed that the conductivity values depended on the content of aqueous solution, while the viscosity values on the physical structures of microemulsion formation.