Abstract: Pulmonary aspiration is a common disease of respiratory system. The morbidity and mortality of the disease is high since it lacks typical clinical symptoms and generally can hardly be detected until severe lung damages caused. Consequently, early diagnosis of pulmonary aspiration is of vital importance. The pathogenetic mechanism of pulmonary aspiration is complicated and diverse. Since its clinical features are not atypical and specific diagnostic method is not available, there are lots of patients delayed in diagnosis and treatment. In the European and American countries, radionuclide imaging is the most commonly used clinical method for pulmonary aspiration diagnosis. However, there are few related researches and reports in China. The writer has summarized the progress of radionuclide imaging for pulmonary aspiration diagnosis.