A 42-year-old male was admitted for paroxysmal syncope for 10 months, chest tightness for 20 days and chest pain for 10 days. The patient was diagnosed with hypertrophic cardiomyopathy. The patient did not have a history of hypertension or diabetes. Coronary angiography and left ventricular cardiac catheterization were done in order to examine the coronary artery and the pressure gradient of the left ventricular outflow tract. The cardiac catheterization was performed via a right radial artery approach and a total of 200 mL of 370 mg I/mL iopromide was injected. The patient developed contrast-induced encephalopathy following the cardiac catheterization procedure, displaying severe headache, cortical blindness and neuropsychiatric symptom as the main clinical manifestations. The patient was then given symptomatic and supportive treatment, including decreasing intracranial pressure, analgesics and sedatives, and the patient recovered.