We obtained Herschel PACS and SPIRE images of the thermal emission of the debris disk around the A5V star {beta} Pic. The disk is well resolved in the PACS filters at 70, 100, and 160 {mu}m. The surface brightness profiles between 70 and 160 {mu}m show no significant asymmetries along the disk, and are compatible with 90% of the emission between 70 and 160 {mu}m originating in a region closer than 200 AU to the star. Although only marginally resolving the debris disk, the maps obtained in the SPIRE 250 - 500 {mu}m filters provide full-disk photometry, completing the SED over a few octaves in wavelength that had been previously inaccessible. The small far-infrared spectral index ({beta} = 0.34) indicates that the grain size distribution in the inner disk (<200AU) is inconsistent with a local collisional equilibrium. The size distribution is either modified by non-equilibrium effects, or exhibits a wavy pattern, caused by an under-abundance of impactors which have been removed by radiation pressure.
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