Substernal goiter is usually defined as a goiter in which the thyroid mass has descended the plane of the thoracic inlet or if more than 50% of the thyroid mass is located below the thoracic inlet. Substernal goiters may be asymptomatic or may present with symptoms caused by compression of adjacent organs. Acute respiratory failure is rare in cases of substernal goiter. In cases of symptomatic substernal goiter the treatment is surgical by thyroidectomy. We present a rare case of a giant substernal nontoxic goiter which caused acute respiratory failure which was treated by urgent thyroidectomy through a T-incision.