Objective: To clarify the profile of cognitive dysfunction and the effects of intensive exercise in spinocerebellar degeneration (SCD). Methods: We enrolled 60 healthy controls and 16 patients with purely cerebellar type SCD without gait disturbance or organic changes other than cerebellar changes. To assess cognitive function, we evaluated the participants using the Mini-Mental State Examination (MMSE), Frontal Assessment Battery (FAB), and Montreal Cognitive Assessment-Japanese (MoCA-J) at admission and after intensive exercise. Results: Compared to the controls, SCD patients showed significant cognitive decline. As a result of intensive exercise, significant improvements in motor and cognitive functions were observed: the MMSE score improved from 27.7±1.9 to 29.0±1.3 points (p<0.001); the FAB score improved from 14.8±2.2 to 15.8±2.0 points (p=0.002); and the MoCA-J score improved from 24.6±2.2 to 26.7±1.9 points (p<0.001). For sub-scores, significant improvements were noted in serial 7, lexical fluency, motor series, and delayed recall. Conclusion Our study indicates that intensive exercise can be effective not only for motor dysfunction but also for cognitive dysfunction (Clinical Trial Registration No. UMIN-CTR: UMIN000040079).