Objective To study visual global and local cognitive functions in the patients with Parkinsons disease(PD).Methods The visual cognitive software,which was devised by the Cognition Laboratory of National Science and Technology University,was used.30 PD patients and 31 normal controls(NC) were enrolled in the study.Result No significant difference on reaction time(RT) of visual global and local processing was found between PD patients and NC.Furthermore,the PD patients were divided into two groups:left side onset(LPD) and right side onset(RPD).The RT was longer in PD than in NC and RT was shorter in RPD than in NC.But there were no significant differences between PD patients and NC except global processing(big and small arrows at the same direction) in LPD.The RT was significantly longer in LPD than in RPD except local processing(big and small arrows at different direction)(P< 0.05).Conclusion The present study indicates that right basal ganglion might play a role in global and local processing and left basal ganglia might modulate(inhibit) the processing activity of right side.