Objective To investigate application effect of CT and MRI in early diagnosis and differentiation of tumor adjacent to the skull space. Methods In this study, the clinical data of 48 patients with tumor adjacent to the skull space in our hospital from January 2015 to January 2017 were retrospectively analyzed, all patients received CT and MRI examinations. Results The pathological diagnostic accuracy of CT in neurilemmoma, deep-lobe parotid tumors, neurofibroma, parotid cyst, carotid aneurysm, and hemangioma were 82.35%, 77.78%, 61.11%, 25.00%, 50.00%, and 50.00% respectively. And those of the MRI examinations were 94.12%, 88.87%, 91.67%, 100.00%, 75.00% and 66.67% respectively. The CT images of schwannoma showed round or oval with smooth boundary and complete capsule, while the carotid aneurysm featured an involvement of the jugular foramen. MRI examination showed that the deep-lobe parotid tumors compressed parapharyngeal space in shift, the neurofibroma had clear boundaries with deep-lobe parotid tumors. The enhanced scan results found uneven high signal in T2WI and oval signal with low density in T1WI. Conclusion Both CT and MRI can diagnose the tumor adjacent to the skull space with its own image features, while the combination of the two examinations can differentiate the pathology characteristics of the disease, which is recommended.