Household food insecurity is independently associated with adverse health outcomes among Canadians, but its association with overweight and obesity is poorly understood partly because of limited attention to confounding. This study assessed the relationship between food insecurity status and overweight/obesity in Canada. Cross-sectional data for individuals aged 2-64 years were drawn from the 2004 and 2015 Canadian Community Health Survey-Nutrition. Overweight/obesity was defined using body mass index calculated with measured height and weight. Food insecurity status was assessed with the 18-item Household Food Security Survey Module. The relationship was examined among preschool children (n=2007), girls (n=5512), boys (n=5507), women (n=8317), and men (n=7279) using propensity score weighted logistic regressions to control for confounding. Relative to their food-secure counterparts, girls in moderately food-insecure households (39.7%vs. 28.5%), boys in severely food-insecure households (54.4%vs. 35.0%), and women in moderately and severely food-insecure households (58.9% and 73.1%vs. 50.7%) had higher overweight/obesity prevalence; men in moderately food-insecure households had a lower prevalence (48.9%vs. 66.3%). With propensity score weighting, no association existed between food insecurity and overweight/obesity among preschool children, girls, boys, or men. For women, moderate (adjusted odds ratio (AOR): 1.61; 95% confidence interval (95%CI): 1.06-2.47) and severe (AOR: 2.33; 95%CI: 1.22-4.44) food insecurity was positively associated with overweight/obesity; the association was strongest for severe food insecurity and obesity (AOR: 3.38; 95%CI: 1.60-7.16). Additional research is needed to better understand the nature of the relationship among women. Problems of food insecurity and overweight/obesity among Canadian children and men should not be conflated in public health interventions.