This dataset from Taipei Veterans General Hospital represents the most comprehensive collection of brain metastases MRI data in the country. It includes axial SE T1WI+C images annotated according to the standard DICOM-RT structure set (RTSS) format, used in both clinical evaluations and Gamma Knife treatments of intracranial metastatic tumors. Each case in the dataset comprises T1-weighted images (T1W), T2-weighted images (T2W), and T1 post-contrast weighted images (T1W+C). The dataset is notable for the high number of cases and the exceptional completeness and precision of the annotations, making it one of the most extensive and detailed brain metastases datasets globally. This allows for a diverse range of AI research projects.