The thyroid gland is a tissue organ of the human body and is the largest secretory gland that secretes thyroid hormones, which plays a very important role in the human body. The thyroid gland is located in the neck, precisely below the thyroid cartilage, on both sides of the trachea. The thyroid gland is mainly composed of two lateral lobes and an isthmus, and is generally soft in texture, but will become hard if there are nodules or swellings. If the thyroid gland is significantly enlarged, you can see that the neck is thicker, which indirectly indicates the location of the thyroid gland. Since the thyroid gland is located in the neck, it can easily cause pressure on the trachea, esophagus, and surrounding nerves, thus affecting breathing, eating, and pronunciation. Although the thyroid gland is located in the neck, its secretion of thyroid hormones affects the metabolism of the whole body, such as hyperthyroidism, which can cause increased excitability and hyper-metabolism in the nervous, circulatory and digestive systems, and hypothyroidism, which can cause systemic hypometabolic syndrome. Therefore, the thyroid gland is located in the neck, but its impact is systemic. If you experience discomfort or feel something hard in the neck, you need to go to the hospital for a thyroid ultrasound and thyroid function test.