OBJECTIVE: Lumbar upward migrated foraminal disc herniations are extremely rare and technically challenging to operate. In this study, a contralateral approach using unilateral biportal endoscopy, which has the advantages of structural protection, efficacy, and safety is presented. METHODS: Between 2019 and December 2022, five patients with lumbar upward migrated foraminal disc herniations underwent unilateral biportal endoscopic discectomy via the contralateral approach. The patients were 4 males and 1 female patient. All patients had severe radicular pain. Neurological examination revealed sensory impairment and motor weakness in 2 patients but no deficits in the others. Magnetic resonance images confirmed lumbar upward migrated foraminal disc herniations in all patients. RESULTS: The study shows a significant reduction in Oswestry Disability Index. Symptoms improved immediately after surgery in all patients, and satisfactory results were achieved at the last follow-up. No surgical complications or recurrent herniations were observed. The mean preoperative Oswestry Disability Index decreased from 44.6 to 11.4. In addition, mean preoperative Visual Analog Scale declined from 8.4 to 1.6. The patients were assessed after a follow-up period of at least 22 months, and their level of pain level was documented. CONCLUSIONS: Although unilateral biportal endoscopic discectomy via the contralateral approach is not a common surgical procedure, it can offer a viable alternative for patients with lumbar upward migrated foraminal disc herniations.