Iron oxide gamma-Fe2O3 nanoparticles were synthesized in aqueous solutions and the equilibrium pressure-area isotherms of the Langmuir layers of stearic acid/gamma-Fe2O3 nanoparticle complexes at the air-water interface were studied. In comparison to a pure water subphase, the surface pressure versus the specific area isotherm of the stearic acid was significantly expanded in the presence of the iron oxide nanoparticles in the subphase indicating the existence of interactions between the stearic acid monolayer and the iron oxide nanoparticles. Stearic acid/gamma-Fe2O3 nanoparticle complex monolayers were transferred onto ZnSe and quartz plate substrates from the air-water interface using the Langmuir-Blodgett (LB) technique and the LB films were characterized with FTIR and UV-vis spectroscopy. From the FTIR studies it was observed that complexation between gamma-Fe2O3 nanoparticles and stearic acid occurred by electrostatic interactions between the carboxylate ions of stearate and the nanoparticle surface. Using UV-vis spectroscopy, the optical absorbance increased linearly with the number of complex LB layers, which indicated that the multilayer complex LB films were deposited uniformly.