The adsorption of natural organic matter (NOM) from eight typical Chinese surface waters onto alumina was investigated using quartz crystal microbalance with dissipation monitoring (QCM-D). The adsorbed masses of NOM varied between 25 ng cm(-2) and 64 ng cm(-2), and these showed significant correlation with geographical location, and NOM character and concentrations. Adsorbed mass correlated with DOC concentration (slope k = 0.0676, R-2 = 0.61) and hydrophobic acid (HoA) and weakly hydrophobic acid (WHOA) (k = 0.0342 and 0.0183; R-2 = 0.49 and 0.52 for HoA and WHoA, respectively) constituents present in the water samples. The process of adsorbed layer formation was investigated from changes in the Delta D/Delta f ratio and viscosity of adsorbed layer with injected time. The adsorbed layer viscosity increased exponentially with injected time (R-2 > 0.99) for most samples. Samples with low DOC concentration (k = -1091.8, R-2 = 0.55) and low content of HoA and WHoA (k = -524.33 and -322.76; R-2 = 0.41 and 0.64 for HoA and WHoA, respectively), the slope of logarithm viscosity value is steeper, the property of adsorbed layer and NOM is more inconsistent. The QCM-D technique provides a method to view the process of complexation between NOM and coagulant, and can provide useful information to establish a quantitative calculation model of the coagulation process. (C) 2012 Elsevier B.V. All rights reserved.