Permittivity and permeability values of thin film Nickel-Zinc ferrite samples deposited on a glass substrate have been derived in the higher microwave frequency range. This thin film has been fabricated by the spin spray process. The thickness of the thin film has been measured to be 0.6 μm. It is deposited on to the 0.2 mm glass substrate. In the lower GHz frequency range, this sample has been observed to exhibit higher permeability than the Snoek's limit of bulk Ni-Zn-ferrite film. The transmission-reflection method based in-waveguide measurement technique has been employed to obtain the scattering parameters in the frequency range from 18 to 40 GHz. The evaluation method for calculating the material properties has been modified to obtain reliable results for thin film based samples. The in-waveguide based measurement technique has been successfully employed for the measurement of the constitutive properties of thin film ferrite samples.