A common spinal condition known as lumbar disc herniation (LDH) can result in radicular and low back discomfort. A 27-year-old man was admitted to our hospital with a 6-year history of persistent low back pain, and his low back pain had recurred with radiation to his lower extremities over the last two months. An extensive right-sided paracentral disc herniation in the L5/S1 intervertebral region, which compressed the nerve root, was discovered by magnetic resonance imaging (MRI) of his lumbar spine. After receiving conservative treatment, the patient reported that his lower back discomfort and neurogenic claudication had gradually subsided after 4 months. After one year, a follow-up MRI showed that the massive, prolapsed disc herniation at the L5/S1 level had totally disappeared. The sagittal protrusion length of the L5/S1 intervertebral disc shrank from 12.35 mm to 3.49 mm. However, there remained a chance of vertebral height loss. During the course of treatment, the height of the L5/S1 intervertebral space was still slightly reduced. The intervertebral space height declined from 7.705 mm to 7.201 mm after one year of treatment. The current case and a review of the literature demonstrate that LDH can decrease with conservative therapy over a short period of time. We stress the effectiveness of conservative treatment in very select LDH cases that lack a clear surgical justification.