Provided is halloysite powder having a small b value. The halloysite powder is powder including a granule in which halloysite including halloysite nanotubes is aggregated, the granule has a first pore deriving from a tube hole of the halloysite nanotubes and a second pore different from the first pore, and the Fe.sub.2O.sub.3 content is not more than 2.00 mass %.