The goal of this study was to assess the association between features of the built environment and levels of walking and cycling as forms of transportation in the city of Curitiba, Brazil. Data collection was conducted through a telephone survey in 2008. The International Physical Activity Questionnaire was used to identify walking or cycling as forms of transportation. The built environment characteristics were obtained through the Geographic Information System for 1,206 adults. Density indicators were computed, considering a radius of 500 m around each individual's household. For the accessibility measures, the shortest distance to selected built environment features (e.g., bus stop, bike path) was used. The association between characteristics of the environment and the practice of walking or cycling was assessed through logistic regressions. After considering individual characteristics, higher-income areas (OR = 0.56, 95 % CI = 0.41-0.76), higher density of Bus Rapid Transit stations (OR = 1.50, 95 % CI = 1.22-1.84), and the proportion of residential (OR = 1.25, 95 % CI = 1.02-1.53) and commercial (OR = 1.47, 95 % CI = 1.13-1.91) areas were associated with any walking prevalence (≥ 10 min/week). Higher access to bike paths (OR = 0.80, 95 % CI = 0.64-1.00) was inversely associated with walking at recommended levels (≥ 150 min/week). Higher-income areas (OR = 0.26, 95 % CI = 0.08-0.81), greater number of traffic lights (OR = 0.27, 95 % CI = 0.09-0.88), and higher land use mix (OR = 0.52, 95 % CI = 0.31-0.88) were inversely associated with cycling. The neighborhood built environment may affect active commuting among adults living in urban centers in middle-income countries.