Lumbosacral perineural cysts are formed by the arachnoid membrane of the nerve root at the lumbosacral level. Most of these cysts are asymptomatic and are found incidentally during computed tomography (CT) or magnetic resonance imaging (MRI) for other causes of chronic lower back pain. This type of cyst requires a differential diagnosis to distinguish it from other causes of radiating pain and neurological symptoms. In the present case, a symptomatic lumbosacral perineural cyst was found, and pain relief was achieved by non-surgical treatment. A lumbosacral perineural cyst was identified from a differential diagnosis of a lumbar disc disorder that presented as radiating pain and neurological symptoms.