Objective To evaluate the differential diagnosis value of enhanced multi-slice spiral CT (MSCT) scan on adrenal adenoma and metastases in patients with malignant tumor.Methods Thirty-nine malignant tumor patients complicated with adrenal nodules were chosen, and all patients underwent MSCT plain scan and enhanced scan.Features of adrenal adenomas and metastases of MSCT enhanced were analyzed.Results Forty-nine adrenal gland nodules were found in 39 patients, and 35 adrenal metastasis were found in 25 patients.They were shown quasi-circular, oval or irregular shaped nodules.The average diameter was (2.6 ± 0.7) cm.Part of them were uneven density, and the CT value of the solid part was (32.8 ± 6.1) Hu.The solid part of tumor in enhancement scanning arterial phase was underwent mild to moderate strengthening, and the CT value was (49.5 ±6.9)Hu.The solid part of tumor was underwent further strengthen scanning in the venous phase, and the CT value was (74.9 ±8.0)Hu.The average CT value of solid part in after 3 min scanning tumor was (72.4 ± 7.6) Hu.Fourteen adrenal adenomas were found in 14 patients.CT value was (19.6 ± 4.5) Hu, and tumor diameter was (1.8 ± 0.4) cm.Enhanced scanning the tumors showed mild to moderate homogeneous enhancement in arterial phase, the CT value was (43.8 ± 8.1) Hu.Venous phase enhanced obviously, the average of CT value was (67.7 ±9.2)Hu.The strong degree in the delay period was decreased significantly, the average value of CT was (55.9 ± 8.8) Hu.The adrenal metastasis tumor diameter (t =4.006, P ＜ 0.001), CT value of plain scan (t =7.320, P ＜ 0.001), CT value of arterial phase enhanced scan (t =2.486, P =0.017) , venous phase enhanced scan (t =2.727, P =0.009) and CT value of the delay period (t =6.653, P ＜ 0.001) were higher than those in adrenal adenoma.Conclusion Enhanced MSCT scan can reflect the hemodynamic changes of adrenal lesions, and provide the bases for the differential diagnosis of enhanced MSCT scan on adrenal adenoma and metastases in patients with malignant tumor.