An indirect horseradish peroxidase immunohistochemical technique was used to identify neurofilaments protein-immunoreactive fibers in lumbar spine ligaments, from patients who underwent spinal surgery for disc herniation. Histologically, neural elements were abundant in all ligaments examined. In the ligamentum flavum the neurofilaments protein-immunoreactive nerve fibers were located especially close to blood vessels and fat globules. Bundles of nerve fibers were seen in all ligaments specimens except those from the ligamentum flavum. Supraspinous ligament and lumbodorsal fascia show also individual axons and free nerve endings. Contrary to the gold chloride impregnation method, immunohistochemical staining revealed no recognizable sensory corpuscles in these ligaments. This can be explained by the lack of immunoreaction of both the capsule of sensory corpuscles and the perineural sheaths of nerve fibers.