Osteomas involving the anterior cranial base are quite rare lesions. Intracranial and orbital extension of these tumors, causing neurological and ophthalmological symptoms and signs is a rare event. Two such cases are reported. In the first one, the tumor arose from the frontal sinus and extended upward to the medial and superior wall of the right orbital cavity and the lower part of the right frontal convexity. In the second case the osteoma arose from the left orbital roof and extended to the lower part of the homolateral frontal convexity and the splenoid wing. After the operation the symptoms disappeared and the cosmetic deficits were corrected. Skull-films, CT and MR well define the bony extension and the displacement of the orbital and intracranial structures. Indications to the surgery include progressive ophthalmologic and neurologic signs and significant cosmetic deformations. The surgical techniques and the postoperative complications are briefly discussed.