Particularities of the spin-wave spectrum in YIG film with the thickness of 0.4 μm and magnetization of 1.1 kG that was corrugated due to the periodical substrate relief in the form of grooves having width of 10 μm, depth of 0.5 μm, sloped walls and period of 20 μm were studied with the help of micromagnetic modelling. Calculations were carried out for the external magnetic field applied along (θ=0) and across (θ=90°) the grooves in the film plane, and showed that the anisotropy from the film form caused the spectrum quantization and localization of spin-wave excitations in the different parts of the sample. Besides that, spacial distribution of magnetization amplitude at fixed frequencies in the spectrum for θ=90° can be characterized by several spacial scales that differ by orders. This is explained by the strong inhomogeneity of equilibrium state at grooves' walls for θ=90° that leads to the effective excitation of short-wave part of the spin-wave spectrum in the periodical structure by Schlömann mechanism.