The present invention provides a dielectric film structure having a substrate and a dielectric film provided on the substrate and in which the dielectric film has (001) face orientation with respect to the substrate, and in which a value u in the following equation (1) regarding the dielectric film is a real number greater than 2: u=(C.sub.c/C.sub.a).times.(W.sub.a/W.sub.c) (1) where, C.sub.c is a count number of a peak of a (00l') face of the dielectric film in an Out-of-plane X ray diffraction measurement (here, l' is a natural number selected so that C.sub.c becomes maximum); C.sub.a is a count number of a peak of a (h'00) face of the dielectric film in an In-plane X ray diffraction measurement (here, h' is a natural number selected so that C.sub.c becomes maximum); W.sub.c is a half-value width of a peak of the (00l') face of the dielectric film in an Out-of-plane rocking curve X ray diffraction measurement; and W.sub.a is a half-value width of a peak of the (h'00) face of the dielectric film in an In-plane rocking curve X ray diffraction measurement.