Penetrating injuries to the anterior skull base involving retained foreign bodies are rare and pose significant challenges due to the complex anatomy and potential for neurovascular, orbital, and intracranial complications. This case report describes a 38-year-old male who sustained cranio-orbital trauma, traversing the posterior table, from a 16 cm curved metal rod that penetrated the right orbit and anterior cranial fossa via the posterior table, resulting in a cerebrospinal fluid (CSF) leak and pneumocephalus. Upon presentation, the patient had intact consciousness, right-sided clear rhinorrhea, and limited supraduction of the right eye, with no evidence of globe penetration. CT imaging demonstrated the metal rod traversing the superomedial orbit and posterior table of the frontal sinus into the anterior cranial fossa, with no vascular or brain injury. The foreign body was removed via a endoscopic transnasal approach. The skull base defect (~1 cm) was repaired using a layered collagen matrix technique (DuraGen) as both an underlay and onlay graft, achieving a watertight seal, and the wound was then trans-cutaneously explored and closed. Post-operative care included IV antibiotics, serial imaging, and multidisciplinary follow-up. The patient had no operative complications, demonstrated full resolution of the CSF leak, and had normal eye movements and vision at follow-up eight weeks post-surgery. This report demonstrates the safety and effectiveness of the trans-nasal endoscopic approach for the removal of a penetrating cranio-orbital foreign body, allowing for simultaneous repair of anterior skull base CSF, avoiding an open surgical approach. This patients’ outcome highlights the importance of multidisciplinary collaboration in managing complex sino-orbital trauma and achieving optimal patient recovery.