The waveguide properties of a thin film separating two elastic half‐spaces possessing a shear modulus higher than the shear modulus of the film are investigated. It is shown analytically and experimentally that such a film is capable of localizing the energy of elastic waves near the interface. The velocity of the interface wave is determined by shear modulus, density, thickness of the film, and by the elastic properties of the substrates. The velocity of the interface wave lies between that of the Rayleigh and that of the shear waves in the solid half‐spaces. It is shown that the interface wave can be used to estimate the elastic and dissipation properties of thin interface layers.