The patient was diagnosed with "motor retardation for 3 years" in the neurology department of our hospital,accompanied by static tremors and ataxia. Physical examination showed that there was a tendency to decrease for amplitude of repetitive finger movements of the left hand and the left hand clenched fist and toe tapping movements were slightly slower. The left heel knee tibia test and rotation test were not accurate,and the father and elder sister had similar symptoms. After admission,laboratory tests such as urinary tract ultrasound and residual urine in the bladder were completed,and the tests did not reveal any significant abnormalities. Brain MRI shows scattered non-specific white matter changes in the left parietal lobe. Levodopa challenge test was positive. The patient was then suspected to have Parkinsonism. considering that the patient has a family history. Genetic testing was ordered and the results showed abnormal amplification of the ATXN2 gene CAG sequence. Therefore,the final diagnosis was spinocerebellar ataxia type 2. The patient's symptoms are stable and there is no progression during the follow-up. SCA2 should be considered in the case of Parkinsonism accompanied by ataxia and a family history to avoid misdiagnosis and missed diagnosis.