Levodopa is the principal pharmacological treatment for Parkinson's disease (PD); however the protein content in diet may compromise its effectiveness. The aim of this study was to investigate the relationship of protein intake and the use of levodopa in ambulatory patients with PD. Thirty four PD patients were assessed for protein intake, evaluating the relation energy-protein intake by means of a register. An intake of 1762 kcal/day, 70.9 g of protein/day equivalent to 16.6% of the total energy intake as protein at a level of 1.1 g/kg bw/day. Of all patients, 47.1% took their medications with meals. We conclude that the studied patients consume more protein in their diet than those recommended for PD, with half the sample taking the medications with meals, which may affect the treatment.