A 1.8 kg, seven months old, intact, female, mix-breed cat was referred with dyspnea and paresis. Since the patient was in such a condition that she was too incapable of the operation, treatment for dyspnea was performed. The patient has abdominal enlargement. When the respiratory stress of the patient decreased, a radiograph was taken and lordosis was found. Medical treatment was applied, because the general condition was impaired. Lordosis is the excessive curvature of a certain number of vertebrae in the neck and back region. Congenital thoracic lordosis has been described as a highly progressive and low vital capacity disease in humans and cats. Because it compresses the lung, it can cause dyspnea in patients and rhythm disturbances in the heart. This case represents a severe example of untreatable and unmanageable lordosis encountered in a cat.