Objective To explore the role of energy spectrum CT in the diagnosis and treatment of pulmonary aspergillosis. Methods From the 130 patients diagnosed with pulmonary aspergillosis by pathological biopsy from 2016 to 2017, 65 patients were selected as the control group, and only blood mold was used for re-examination. Another 65 patients were selected as the study. In the group, in the re-examination, the energyspectrum CT was used as the basis of the control group. The same treatment regimen was used in the two groups of patients, ie, oral itraconazole was given intravenously with caspofungin. After a six-week treatment, whole blood samples from two groups of patients were collected, blood mold culture was performed, and the positive detection rate of pulmonary aspergillosis was counted. All patients applied energy spectrum CT for retest. The treatment efficiency of the two groups of patients was counted. Results The different methods were used before the treatment. The accuracy of the study group was significantly higher than that of the control group (P<0.05). After treatment, the positive detection rate of blood mold culture in the two groups was significantly lower than that before treatment (P<0.05). The reproducibility of the study group was significantly higher than that of the control group (P<0.05). Conclusion In the diagnosis and treatment of pulmonary aspergillosis, the use of energy spectrum CT can effectively improve the accuracy of diagnosis, and it is of great help to doctors to determine the treatment plan of patients, and has great application value in clinical.