Fifty-six patients with parotid masses, benign tumors in 22, malignant tumors 26 and other diseases 8, were examined by CT scan, which can differentiate intrinsic from extrinsic parotid lesions, especially deep lobe from parapharyngeal tumors and typical benign tumors from malignant ones, but may fail to differentiate aggressive benign tumors from low-grade malignant ones. CT sialography was done to detect the relation between the trunk of the facial nerves and tumor according to the band of normal parotid tissue between the tumor and posterior border of the mandibular ramus, and incremental dynamic CT with intravenous bolus injection of contrast medium to detect the relation between the tumor and carotid sheath. We conclude that the images of CT sialography are much better than those of plain CT and intravenous enhancement CT.