We herein present the imaging findings in a case of diffuse primary cutaneous B-cell lymphoma of the cranial vault with orbital and brain invasion. MR imaging revealed first concomitant orbital and parenchymal invasion in a case of primary diffuse non-Hodgkin lymphoma of the cranial vault. Contrast-enhanced MR imaging revealed a diffuse mass in the scalp of the frontoparietal region bilaterally and invasion of the right orbit and left frontoparietal lobe. Histologic and immunopathologic examinations revealed diffuse primary cutaneous B-cell lymphoma.