Anisotropic thermal diffusion of polyvinylidene fluoride was calculated in two dimensional analysis and compared to the experimental results. The transient pyroelectric currents due to the lateral heat diffusion in the film were measured when the laser light was projected. Thermal diffusivity in the direction parallel to the stretched direction, k//, was about three times lager than those to the perpendicular direction, k⊥. The k// and k⊥ were about 4.5×10-3cm2 sec-1 and 1.5×10-3, respectively. It was found in calculation and experiments in the pyroelectric vidicon that the spreading of spot images in the stretched direction are about two times larger than that in the perpendicular direction.