Objective To analyze MSCT characteristics of septic pulmonary embolism (SPE) caused by intravenous drug and to improve diagnosis. Methods The MSCT findings of 16 patients of SPE induced by intravenous drug were analyzed retrospectively from March, 2001 to September, 2008. Results Peripheral or sub-pleural zones were commonly affected mainly within upper lung. Patchy, nodular and cavity shadows were detected respectively in 9 (56.25%), 12 (75.00%) and 8 patients (50.00%), while pulmonary cysts in 14 patients (87.50%). Six patients underwent CTPA, and pulmonary arteries filling defect was found in 2 patients. Pleural effusion and pneumothorax were also found in 10 and 3 patients, respectively, whereas miscellaneously shaped lesions were deteced in all 16 patients. Conclusion MSCT is an important method for diagnosing SPE caused by intravenous drug abuse. Pulmonary arteries filling defect is the direct sign and the cysts and nodular shadow with or without cavity in peripheral or sub-pleural pulmonary zones are characteristic findings.