Schwannomas are benign nerve sheath tumors that arise from Schwann cells, which are responsible for producing the myelin sheath that surrounds nerves. They are typically slow-growing and can occur in various locations in the body, including the lumbar region of the spine. We present a case of giant invasive intradural extramedullary schwannoma managed with posterior lumbar interbody fusion (PLIF) and laminectomy with excellent results. A 58-year-old man presented with lower back pain radiating to the right leg for six months. He had no history of trauma or systemic disease. Lumbosacral magnetic resonance imaging (MRI) showed a well-defined mass at the L3-L4 level compressing the right nerve root. The patient was managed with L3-L4-L5 transpedicular fixation and right-side laminectomy L3-L4 for resection of the tumor. Histopathological examination confirmed the diagnosis of schwannoma. The patient had a favorable postoperative recovery and experienced a resolution of symptoms. Lumbar schwannomas are rare they can cause significant symptoms and require appropriate diagnosis and management. Microsurgery is the preferred treatment, and endoscopic microsurgery is the most promising technique.