A process for producing spherical base granules comprising a easily water-soluble drug, which comprises spraying a layering liquid over pharmaceutically inert spherical core particles and coating the particles with a drug-containing layer, wherein: the spherical core particles have a microcrystalline cellulose content of 30 mass% or greater and a water absorbing capacity of 0.5 cm3 /g or greater and the layering liquid is an aqueous solution comprising at least from 5 to 30 mass% of the easily water-soluble drug and from 1 to 30 mass% of a low water-soluble saccharide.
