Mixed Langmuir-Blodgett films of behenic acid and glucose oxidase have been elaborated. The resulting films have been studied by scanning force microscopy with the "tapping" mode, from the micrometer scale to the nanometer scale. The general organization of the mixed film and the enzymatic quasi 2D crystals have been observed. Lateral force microscopy, coupled with topographic data obtained with the contact mode, has made possible the distinction between enzyme and behenic acid domains.