The surface activities and application properties for the mixtures of cationic surfactants tetramethylene-1,4-bis[N,N-bis(hydroxypropyl)-hexa/decyloxypropylammonium] bromide (GC 10 -P) and tetramethylene-1,4-bis[N,N-bis(hydroxyethyl)hexa/decyloxypropylammonium] bromide (GC 10 -E) and anionic surfactant isomeric sodium fatty alcohol ether sulfates (iso-AE 9 S) were investigated using both the tensiometry and the conductometry. The interaction parameters and thermodynamic micellization parameters of GC 10 -P/iso-AE 9 S and GC 10 -E/iso-AE 9 S mixtures were evaluated by Clint−Rubingh and Motomura theoretical models. When the mole fraction of α 1 for GC 10 -P/iso-AE 9 S mixed system was 0.2, the critical micelle concentration (CMC) reached a minimum of 1.61 × 10 −4 mol/L, and the minimum critical micelle concentration of the GC 10 -E/iso-AE 9 S mixed system is 2.67 × 10 −5 mol/L at α 1 = 0.6. The CMC value of the mixed system is 1−2 orders of magnitude lower than that of any single component. The results indicate that the synergistic effects of the investigated mixed systems (evaluated by β m ) are in order of GC 10 -P/iso-AE 9 S < GC 10 -E/iso-AE 9 S, with maximum β m values of −17.98 and −9.78, respectively. The change in zeta potential indicates that the poly(ethylene oxide) chain has weakened the charge density of the hydrophilic headgroup of the anionic surfactant. The interfacial tension at the oil−water interface in the mixed system of anionic/cationic surfactants is lower than that of any single component, exhibiting a higher interfacial activity. The mixed system exhibits a decreased contact angle and superior wetting ability over any single component, and it also enhances foam performance, emulsification performance, and degreasing performance.