We report one woman with acute cerebellar ataxia (ACA), a well-defined clinical syndrome, which occurred 10 days after the second vaccination with recombinant hepatitis B vaccine. The patient had no previous symptoms or signs of neurological disease and there was no evidence of neurologic disease in the family history. Within nine months the symptoms remitted completely according to other reports of ACA. As there was a close temporal connection and no noticeable other cause we assume a causal link between the vaccination and the disease. As far as we known this is the first case of ACA after hepatitis B vaccination.