The aim of this pilot randomized controlled trial was to evaluate the effects of treadmill training on cognitive and motor performance in patients with Parkinson's disease (PD). Seventeen persons with mild to moderate PD were enrolled. Nine patients were allocated to the Intervention group and received twelve 45-minute sessions of treadmill training: one session a day, three days a week, for four consecutive weeks. Eight patients were allocated to the Control group; these patients did not undergo physical training but were required to have regular social interactions, following a specific lifestyle program. All the patients were evaluated at baseline and one month later. The primary outcome measures were the Frontal Assessment Battery-Italian version (FAB-it) and the 6-minute walking test (6MWT). At the one month evaluation significant differences were found between the groups in their performance on the FAB-it (p=0.005) and the 6MWT (p=0.018). Our findings support the hypothesis that treadmill training might effectively improve cognitive and motor features in patients with PD.