Introduction: Tay-Sachs disease is a rare, fatal, autosomal recessive neurodegenerativedisorder caused by ? -hexosaminidase A deficiency , resulting in GM2 ganglioside accumulation and progressive neuronal damage. The disease is more common in Ashkenazi Jewish. Case presentation: A 1-year and 6-month-old girl, born as third child of first-degreeconsanguineous parents, one sibling had neonatal death of unknown etiology , while twin siblings were healthy . Development was mildly delayed until 5 months, after which she lost previously acquired milestones, particularly gross motor and social skills. By 18 months, she had no head control, visual tracking, palmar grasp, or babbling, and responded only by crying. Her first seizure occurred at 12 months following immunization, progressed from focal to generalized seizures. Despite optimum dose of sodium valproate and levetiracetam seizure control remained poor. Examination revealed macrocephaly , severe wasting. Neurologically she had generalized hypertonia, brisk reflexes, bilateral extensor plantar responses, dystonia, wandering eye movements, and exaggerated startle reflex. No organomegaly was detected. Fundoscopy showed bilateral cherry red spots with early optic atrophy . MRI brain demonstrateddiffuse white matter changes, bilateral striatal hyperintensity with swelling, and thalamic hypointensity . Enzyme assays and genetic testing were not available due to limited resources. The child was managed conservatively with anticonvulsants, nutritional support, and physiotherapy . The progressive nature of the disease and its poor prognosis were discussed indetail with the parents. Conclusion: Recognition of neuro regression, exaggerated startle response, cherry red spots and characteristic MRI findings enables early diagnosis in resource-limited settings, allowing supportive care and genetic counselling.