Fear of falling is more common and pronounced in people with Parkinson’s disease than in controls. We conducted a series of studies that used multivariable regression analyses to identify explanatory factors of fear of falling in people with Parkinson’s disease. Three independent samples were used. The first study (n=154) was a postal survey study that used well-established self-rating scales. The second study replicated the first one by using a clinical sample (n=104) and added unexplored motor aspects (e.g., gait speed, functional balance performance) as well as global cognition. The third clinical study (n=241) included independent variables that focused on personal (e.g. general self-efficacy) and environmental factors as well as Parkinson-related disabilities. In all three studies, walking difficulties was the strongest explanatory (60–68%) factor. The results imply that walking difficulties in daily life should be the primary target in order to reduce fear of falling in people with Parkinson’s disease.