The nature of protein adsorption by bentonite in a model wine solution was studied. Model wine solution containing bovine serum albumin, water, alcohol and potassium bitartrate was mixed with aqueous bentonite solutions of various strengths. Adsorption equilibrium was established within 30 seconds. Samples were centrifuged, membrane filtered and assayed for protein content. Data were transformed into Langmuir and Freundlich forms and analyzed by linear regression. The interaction of bentonite and protein in a wine-like system has been quantified for the first time. Factors affecting the adsorption process such as protein concentration, solution pH, bentonite type, temperature and alcohol level were quantitatively evaluated.