To verify possible dysfunction of sympathetic skin activity in Parkinson's disease (PD), we studied the electrically evoked sympathetic skin responses (SSR) bilaterally at hands and feet in a group of 50 PD patients and in normal subjects. SSR was present in all patients. Nevertheless, significant differences in the latency and amplitude values were noted. In the group of patients prolongation of latency as well as the reduction of SSR amplitude correlates with age. The longer the disease the more SSR abnormalities could be found. Gender, type of clinical manifestation of PD or medication had no statistically significant effects. However, motor symptom asymmetries evaluated separately for each body side correlated well with interside asymmetries of SSR.