We report a case of difficult lumbar puncture due to the inability to obtain adequate cerebrospinal fluid (CSF) in a patient later diagnosed with spinal epidural lipomatosis (SEL). A 76-year-old man with a body mass index (BMI) of 24.1 kg/m2 was scheduled for transurethral resection of a bladder tumor for superficial bladder cancer under spinal anesthesia. The patient had a 3-year history of inhaled steroid use for the management of chronic obstructive pulmonary disease. After placing the patient in the right lateral position, a lumbar puncture was performed via the median approach. However, CSF could not be tapped adequately despite repeated attempts at lumbar puncture, so general anesthetic was administered instead. Subsequently, both anesthesia and surgery proceeded uneventfully. On the first postoperative day, the patient developed mild postdural puncture headache (PDPH), which was treated conservatively. No postoperative neurological complications related to spinal anesthesia were observed. Approximately 2 months after discharge, the patient reported progressive lower back pain and was diagnosed with SEL by magnetic resonance imaging (MRI). A lumbar laminectomy and removal of excessive adipose tissue was performed. After surgery, the patient's symptoms resolved. The pathogenesis of SEL involves excess fat tissue deposition in the spinal canal, which can lead to obliteration of the spinal subarachnoid space. Therefore, in this patient, the SEL was thought to have caused the inability to obtain adequate CSF during lumbar puncture, and was associated with difficult spinal anesthesia.