Abstract Experimental characterization of the dielectric properties of a SrTiO 3 ( STO ) thin film in the microwave frequency range at room temperature is presented. The coplanar waveguide linear resonator technique, which is already well‐established for thick film characterization, was tailored and improved to allow thin film measurements. Experimental results are in very good agreement with theoretical analysis. Using this approach, a relative dielectric constant of 95 and a loss tangent less than 10 −3 were measured for a STO film with 4.2 μm of thickness deposited by radio frequency (RF) magnetron sputtering. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:2418–2422, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26233