The objective of this study was to describe the functional profiles of patients with Parkinson's disease (PD), and the relationships between impairment in body functions, limitations in activities, and environmental factors, using the World Health Organization's International Classification of Functioning, Disability, and Health (ICF). Patients were consecutively enrolled, and the ICF checklist was administered. Two count-based indices were developed: "extension", containing ICF categories rated with qualifiers 1-4 and "severity", containing ICF categories rated with qualifiers 3-4. Categories rated with qualifiers 1-4 in at least 50% of patients are described separately. Spearman's correlation analysis was carried out to identify the relationships between impairments in body functions (BF) and body structures, activities and participation, and environmental factors (EF); linear regressions were performed to identify the best predictors of performance indices in activities and participation. A total of 96 patients were enrolled; 34 categories rated with qualifiers 1-4 in at least 50% of patients are reported, and most of them describe impairment in movement-related functions and limitations in mobility and self-care. Performance indices are significantly lower than capacity and significant relationships with both BF impairments and EF are observed. High difficulties in activities and participation performance are connected with both presence of severe BF symptoms and relevant barriers in EF. Both BF and EF play a relevant role in improving functioning of the patients with PD. The connection between EF barriers and severe problems in activities and participation performance suggests the need of fostering participation of patients with PD by promoting facilitators among EFs. Methodologies and tools are needed to couple information on symptoms, on the difficulties in executing activities, and on environmental features.