The system (sodium dodecyl sulfate (SDS)-hydrolyzed polyacrylamide AD37-poly(4-vinylpyridine (P4VP)) in aqueous media for the fixed AD37 concentration at T=25°C, was investigated using conductivity measurements. The characteristic concentrations of the surfactant-polyelectrolyte-polyelectrolyte complexation: the critical aggregation concentration (CAC) and saturation of the polyelectrolyte complex (AD37/P4VP) by SDS (X2) were determined from the curve of conductivity according the concentration of surfactant. In the presence of the complex (AD37/P4VP), the relationship between conductivity and SDS concentrations shows two breaks of slope.