The invention discloses a capsule preparation for treating thyroiditis, which is prepared from the following raw materials in parts by weight: 25 parts of honeysuckle, 20 parts of Anemarrhena, 20 parts of forsythia, 10 parts of Shegan, 10 parts of Luzon fruit, magnolia 10 parts, 15 parts of Alisma, 25 parts of white peony, 15 parts of Eucommia leaves, 20 parts of Tongcao, 15 parts of roselle, 15 parts of Scrophulariaceae, 10 parts of turtle shell, 30 parts of astragalus, and 15 parts of lotus seeds. The preparation method is as follows: taking various raw materials, mixing, adding water, decocting, filtering, adding water to the filter residue, decocting, filtering, merging, concentrating under reduced pressure, drying, and packing into capsules to obtain the product. The capsule preparation for treating thyroiditis of the present invention mainly treats Hashimoto's thyroiditis. During treatment, it is taken orally twice a day, once in the morning and once in the evening, and the oral dosage is 3 to 5 grams. 15 days a course of treatment. Generally, 3 to 4 courses of treatment can be cured.