Abstract: The authors made a research on the dispersibilities of γ-Fe₂O₃ treated by three kinds of surfacetants. The characters of adsorption of the surfacetants are studied by thermogravimetry-differential thermal analysis. It is found that the temperature,enthalpy, and energy of activation of phase transition from γ-Fe₂O₃ to α-Fe₂O₃ distinctly change after desorption of different surfacetants from γ-Fe₂O₃. Thus this phenomenon can be used to judge between chemical and physical adsorption. We find that two kinds of surfacetants of chemical adsorption can improve the dispersibility of γ-Fe₂O₃ in toluene-butanone.