Spinal muscular atrophy (SMA) is a disease characterized by progressive loss of motor neurons causing progressive muscle atrophy. To date, no definitive treatment is available, and management primarily involves symptomatic treatment, such as artificial ventilation for respiratory failure, among other such strategies. Nusinersen, a new drug that was introduced in Japan in 2017, can improve motor function in these patients. However, nusinersen needs intrathecal administration, which serves as a disadvantage. Lumbar puncture for intrathecal administration can be challenging in patients with advanced scoliosis. We report 2 cases of X-ray fluoroscopic-guided lumbar puncture performed in patients with SMA and concomitant advanced scoliosis. Case 1: A 29-year-old woman with SMA and advanced scoliosis underwent successful lumbar puncture using X-ray fluoroscopy for intrathecal administration of the drug. Case 2: A 15-year-old female adolescent with SMA and advanced scoliosis was scheduled for intrathecal drug administration, and the drug was successfully administered under fluoroscopy guidance, as in case 1. We conclude that X-ray fluoroscopy is useful for lumbar puncture in patients with advanced scoliosis.