Calcified foci of the thyroid are mostly strong echogenic shadows found on imaging tests such as thyroid ultrasound, which are actually the result of calcium salt deposits. Calcified thyroid foci may be benign or malignant thyroid lesions. 1. In some nodules with coarse calcification or marginal calcification, the acoustic shadows due to calcification can make the internal features of the nodule unrecognizable. According to the TIRADS guidelines, these nodules can be evaluated as at least TIRADS category 4 with a risk of malignancy of >5%. 2. Uncountable numbers of microcalcifications within the thyroid nodule, known as “blizzard-like” microcalcifications. These calcifications have a 100% specificity for malignancy and are therefore evaluated as TIRADS category 5. 3. The presence of large, diffusely distributed, numerous punctate calcified echoes within the thyroid parenchyma, either unilaterally or bilaterally, typically with a “blizzard-like” appearance, is commonly associated with diffuse sclerosing papillary carcinoma of the thyroid gland. It is recommended that patients who have found calcified foci of thyroid on examination should consult with specialists in time to judge their conditions according to the size and shape of the calcified foci, and follow the doctor’s instructions for further examination or treatment.