Background: We performed a follow-up study of an acute organotin poisoning case on the neurological sequelae that remained after 3 years since diagnosis. Case: In the previous study, a 43-year-old male was reported for acute organotin poisoning. After 3 years, the neurological sequelae were studied using neurological examination, cognitive tests, neurobehavioral tests (by CAYSYS 2000™), brain magnetic resonance imaging (MRI), and ¹?F-fluorodeoxyglucose (¹?F-FDG) PET/CT. Upon neurological examination and other tests, orientation was improved compared to that 3 years before, but cerebellar ataxia, dysmetria and dysdiadochokinesia remained the same, with little change. Brain MRI showed cerebellar atrophy. ¹?F-FDG PET/CT revealed mildly decreased metabolic activity in the pons and in both cerebellar hemispheres. Discussion: This is the first brain MRI study on cerebellar atrophy caused by organotin poisoning. Cerebellar ataxia was confirmed by decreased metabolic activity in ¹?F-FDG PET/CT.