Whether or not patients can eat fungus after thyroid surgery depends on the nature of the primary thyroid disease. If the primary disease of the thyroid gland is benign, such as thyroid cyst, thyroid adenoma or nodular goiter, patients can eat fungus in moderation after surgery. Wood ear is rich in iodine, which can replenish thyroid hormone levels and keep them within the normal range without causing serious complications. Second, if the patient’s primary disease is a malignant tumor, the entire thyroid gland needs to be removed. After the surgery, the patient may eat more fungus, which may cause the level of thyroid hormone in the body to rise significantly, which may induce the recurrence of thyroid malignant tumor and aggravate the patient’s condition. Therefore, patients with thyroid malignant tumor should not eat fungus after surgery and try to eat non-iodized salt to avoid recurrence of tumor.