The invention relates to the technical field of medicine, and discloses an allopurinol sustained release capsule and a preparation method thereof. The allopurinol sustained release capsule comprises allopurinol, bleached and dewaxed shellac, a blank sphere, povidone K30 and talcum powder. In the invention, the formula ingredients are changed, and appropriate raw materials are selected to combine with the special preparation technology, so as to prepare high-stability allopurinol sustained release preparations which are different in batches and basically identical in the releasing rate.
