The dynamic organization of a mixed Langmuir film of glucose oxidase and behenic acid has been studied. Samples of the mixed film transferred after different relaxation times were analyzed by UV-Vis and IR spectroscopies and by lateral force microscopy. The results demonstrate that the enzyme molecules present at the air/water interface are progressively covered by the behenic acid film. Moreover, we observe an increase of the quantity of glucose oxidase in the mixed film with time, showing that the adsorption of glucose oxidase under the behenic acid film continues during and after the relaxation process.