Objective To study the value of MRI and CT in the diagnosis to rupture of intracranial dermoid cyst, and to improve the understanding of its imaging findings. Methods In the 12 cases of rupture of intracranial dermoid cyst proved by pathology and surgery were retrospectively analyzed, were performed MRI SE T1WI, T2Wl, T2Wl flair and DWI sequence scan, of which three cases T1WI pressure fat enhancement scan, 4 cases brain CT scan. Results Among the 12 cases with intracranial dermoid cyst, located in the CPA 5 cases, 2 cases were identified in the pons before pool, temporal pole is 1 case, beside to the saddle in 2 cases and 2 cases on the saddle, the lesion showed irregular or like-round masses, CT characterized by low density, T1WI for high signal or mixed signal, T2WI for heterogeneous high signal, T2Wl flair for heterogeneous high signal, DWI restricted diffusion, the press fat enhancement scan is not improved. CT and MRI revealed low density fat drop shadow in the sulci, pool or ventricle for rupture of intracranial dermoid cyst, CT value in -70~140HU, or short T1 fat drop shadow, T2WI signal attenuation slightly, the press fat T1Wl enhancement has very low signal, 2 cases lipid droplets in the lateral ventricular, 3 cases located in the longitudinal crack pool, 3 cases located in lateral fissure pools, 2 cases located in lateral fissure pools and longitudinal crack pool, the other 2 cases of lipid droplets in ring pool. Conclusion The rupture of intracranial dermoid cyst show characteristic manifestations on CT and MRI, can show structures and extent of the lesion very well, which is helpful in differential diagnosis and guide treatment plan.