A technique for thermal characterization of anisotropic dielectric films is developed. The technique is applicable to a film which has thickness of the order of 1 mu m and is on a substrate with high thermal conductivity. Metal lines with various widths are deposited on the film using standard IC fabrication processes and are subjected to harmonic Joule heating. Monitoring the resulting amplitude of temperature oscillations in the metal lines allows the determination of the in-plane and out-of-plane thermal conductivity. The present work performs thermometry using the electrical method known as the 3 omega technique and also the thermoreflectance technique. Measurement results are reported for polyimide films on silicon substrates.