The transoral transclival approach for the treatment of intradural lesions of the clivus is often associated with serious complications such as cerebrospinal fluid (CSF) leakage and meningitis. CSF pulse energy may be the most significant factor in CSF leakage and meningitis, but a bone baffle can block such CSF pulse energy. A 64-year-old female presented with sudden onset of severe headache. She had subarachnoidal hemorrhage due to a rupture of the vertebral-posterior inferior cerebellar artery aneurysm. A 66-year-old female complaining of occipitalgia and numbness of the extremities had a foramen magnum meningioma. Both patients were treated via the transoral transclival route with a protective bone baffle, obtained from the iliac bone, securely fixed in the bone window to protect the repaired dura from injury by CSF pulse energy. Neither patient showed CSF leakage or meningitis, and the period of continuous lumbar CSF drainage was only 7 days. The transoral transclival approach with a bone baffle is still very effective in selected cases.