A case of tracheal collapse (TC) within the chest, which was diagnosed by radiograph, was observed clinically in a three years and ten months old male chihuahua dog. This case showed successful reaction to treatment using corticosteroid, bronchodilator and antibiotics during about 28 months in which a period of 12 months consisted of no treatment. At the age of 6 years and 3 months, severe symptoms of TC with respiratory distress with goose honk cough and the protruded tracheal cartilage in the lumen of trachea were observed., The dyspnea was temporarily improved by using a tracheal tube as an emergency treatment, but the patient died on the 4th day after the outbreak of TC. As the pathological changes in the trachea, there were evidence of flattening, stenosis of the trachea, deformation, and protrusion into the lumen of cartilages, hypocellular change and randomly distributed connective tissue fibers in the organic matrix of cartilage, and thickened and flaccid dorsal tracheal membranes. It was considered that this case was a severe grade type, more than grade IV in the classification of TC by Tangner.