Frontal sinus fracture is uncommon but may be a part of complex fracture involving central facial skeletons. The principles of management are (1) observation and consultation with neurosurgeon; (2) proper antibiotics administration; (3) surgery if indicated. The goals of surgery are: (1)restore contour; (2) separate cranial cavity from nasal cavity; (3) prevent late complications such as mucocele. Two cases of frontal sinus fracture treated with sinus ablation and sinus obliteration with cranial bone graft were reported. Proper case selection and meticulous surgical technique were emphasized.