Novel quaternary iminium compounds, namely, N-(4-methoxybenzylidene)-N-benzyldodecyliminium chloride (I a ), N-(4-methoxybenzylidene)-N-benzylhexadecyl iminium chloride (I b ), N-(4-methoxybenzylidene)-N-benzyloctadecyliminium chloride (I c ), and N-benzylidene-N-benzyldodecyliminium chloride, were prepared. The surface properties such as surface and interfacial tension, foaming, and emulsifying power of these surfactants were investigated. The surface parameters including critical micelle concentration (CMC), maximum surface excess ( max ), minimum surface area (A min ), efficiency (PC 20 ), and effectiveness ( CMC ) were calculated. Free energy of micellization ( G o mic ) and adsorption ( G o ads ) were calculated.