Interface activity between liquid and air (liquid/air) of palm-based anionic surfactant sodium laurate methyl ester α-sulphonate (C₁₂MES), cationic surfactant tetradecyltrimethylammonium bromide (TTAB) and their mixtures at various mixing ratio was investigated using surface tensiometer. Variation of surface tension with concentration was used to determine the critical micelle concentration (CMC) of the individual surfactants as well as their mixtures at different mixing ratios. It was observed that the CMC for the mixed surfactants were 10 times lower than its individual counterpart. This showed that the surfactant mixtures were more effective and had higher surface activity than their single components. The surface tension at CMC for surfactant mixtures were around 25 mN m^-1, where as for single surfactants, the value was above 28 mN m^-1. Foaming properties (such as foaming power and foaming stability), wetting and emulsification performance of the mixed surfactant systems was also evaluated at different water hardness in this work. Mixed surfactants especially at equimolar mixing ratio were found to exhibit superior performance as compared to their individual parent surfactants.