Starting from Prussian Blue and an amphiphilic derivative of Ru(bpy)(3)(2+), new organic-inorganic systems have been obtained using the Langmuir-Blodgett (LB) technique. Characterization of the thin films by different techniques (infrared spectroscopy, X-ray diffraction, and transmission electronic microscopy) has demonstrated a strong dependence of LB film organization on the starting concentration of Prussian Blue in the subphase and on the time lapse between Langmuir film spreading and the formation of the LB multilayer. These trends can be ascribed to the slow adsorption of colloidal particles of Prussian Blue along the monolayer and explain the change observed in the low-temperature ferromagnetic properties of these hybrid LB films.