Abstract The conductivity (κ), surface tension (γ), viscosity (η), dynamic light scattering (DLS) and Krafft temperature (KT) measurements of aqueous dodecyltrimethylammonium bromide (DTAB) and di(dodecyldimethylammonium bromide) (12-2-12) with poly (amidoamine) (PAMAM) dendrimers have been carried out at 25 °C. From the κ data, the apparent critical micelle concentration (acmc) for 12-2-12 and DTAB in aqueous PAMAM and complex forming concentration of PAMAM (CS) were computed. Both acmc and CS increased with the increase in [PAMAM] and [12-2-12], respectively. The γ studies indicated a considerable decrease in the γ value for 12-2-12 in aqueous 0 and 1 G than 0.5 and 1.5 G. However, similar γ behavior of DTAB in aqueous PAMAM did not discriminate among various generations. From η studies, the intrinsic viscosities of 12-2-12 ([η]12-2-12) and DTAB ([η]DTAB) for 12-2-12 and DTAB in aqueous PAMAM were computed. Both values were higher for 12-2-12 than for DTAB suggesting stronger association in 12-2-12 + PAMAM complex.