Novel ZnO - Gd3+ materials were prepared by sol-gel method and photoluminescence properties of their films were studied for biomedical application. Biosensor’s properties ZnO - Gd3+ films were investigated under the action of rabbit immunoglobulin G (IgG) in concentrations 10-9, 10-11 and 10-13 M in solution depositing on the surface of film. The doping of ZnO film by Gd3+ in an amount from 1-12 mass.% with increments of 1 mass. % results in significant variations of fluorescence spectra ZnO - Gd3+ films. The ZnO substrate without of Gd3+ compounds allows detecting IgG in a concentration of 10-11 M by fluorescence spectroscopy method by registration in UV region (320-450 nm). By using ZnO - Gd3+ system it was obtained the increase the concentration limit of immunoglobulin (10-13M) detection. In the only case (the content of Gd3+ in ZnO film - 8 mass. %) was observed batochromic shift of fluorescence band maximum by 20 nm (from 364 to 385nm) when interacting with immunoglobulin regardless of the concentration of the last. © 2018 TANGER Ltd. All Rights Reserved.