Neighbourhood characteristics can impact the health of residents. This study investigated associations between objectively derived neighbourhood characteristics, including novel space syntax metrics, and self-reported body mass index (BMI) among Canadian men and women. Our study included survey data collected from a random cross-section of adults residing in Calgary, Alberta (n = 1718). The survey, conducted in 2007/2008, captured participants' socio-demographic characteristics, health, and weight status (BMI). Participants' household postal codes were geocoded and 1600-m line-based network buffers estimated. Using a geographical information system, we estimated neighbourhood characteristics within each buffer including business destination density, street intersection density, sidewalk length, and population density. Using space syntax, we estimated street integration and walkability (street integration plus population density) within each buffer. Using adjusted regression models, we estimated associations between neighbourhood characteristics and BMI (continuous) and BMI categories (healthy weight vs. overweight including obese). Gender-stratified analysis was also performed. Business destination density was negatively associated with BMI and the odds of being overweight. Among men, street intersection density and sidewalk length were negatively associated with BMI and street intersection density, business destination density, street integration, and space syntax walkability were negatively associated with odds of being overweight. Among women, business destination density was negatively associated with BMI. Urban planning policies that impact neighbourhood design have the potential to influence weight among adults living in urban Canadian settings. Some characteristics may have a differential association with weight among men and women and should be considered in urban planning and in neighbourhood-focussed public health interventions.