With over 60 years of development, day surgery (ambulatory surgery), for its efficiency, safety and economic benefits, has been widely carried out in countries with advanced medical technologies such as many European countries and the United States. However, the starting time of day surgery in China is relatively late, and there are few grade-A tertiary hospitals that are performing thyroid day surgery at present. As a result of the increasingly intensive use of the concept of enhanced recovery after surgery (ERAS) in all surgical fields in recent years, ERAS protocols have also been incorporated into the thyroid surgery practice, with remarkable results achieved. Furthermore, the application of various novel techniques in thyroid surgery also improves the surgical safety and reduces the incidence of postoperative complications. Among the total of 56 surgical procedures selected by the first recommendation of the Chinese Ambulatory Surgery Alliance (CASA), 4 types are thyroid procedures. Although there are still some controversies and difficulties in promoting thyroid day surgery in China caused by many factors, it is being gradually recognized and accepted by both the medical practitioners and patient parties, together with a great deal of valuable experience accumulated. Therefore, relevant domestic experts from the Chinese Association of Thyroid Oncology and the Chinese Association of Head and Neck Oncology as well as Chinese Research Hospital Association Thyroid Disease Committee jointly developed the Chinese expert consensus on thyroid day surgery (2021 Edition) after detailed discussions both online and offline, striving for perfection and reaching a general agreement.