Abstract: The author reports two cases of unilateral absent pulmonary perfusion imaging. On the basis of clinical symptoms, laboratory tests, imaging examinations, and pulmonary angiography, the patients were diagnosed with pulmonary arteritis. Pulmonary perfusion imaging can be used as a good testing tool for pulmonary arteritis and has important significance in assessing disease severity and directing further management. This tool plays an irreplaceable role in follow-up and curative effect evaluation.