Food insecurity is a public health concern in high-income countries, including Australia, primarily due to socioeconomic disadvantage, such as low income(1). Living in socioeconomically disadvantaged regions has been associated with poorer diet quality(2). This suggests that characteristics of the community food environment may play an important role in shaping dietary behaviours and food insecurity. However, little is known about how people perceive their local food environment and how these perceptions relate to food insecurity and dietary behaviours, especially in regional areas. This study aims to examine the association between perceived community food environment, dietary behaviour, and food insecurity in the Illawarra and Shoalhaven region of Australia. An online cross-sectional survey was conducted among adults aged 18 years or over. Food insecurity status was determined using the 18-item USDA Household Food Security Survey Module (HFSSM). Perceptions of the community food environment were assessed using 11 Likert scale items (responses from 1= strongly agree to 5= strongly disagree). Dietary behaviours were measured using self-rated overall diet quality (responses: 1 = excellent to 5 = poor), and number of daily servings of fruits, vegetables, and sugar sweetened beverages. A binary food security status was created and categorised as either food secure (HSSFM score=0) or food insecure (HFSSM =1+). Composite scores for perceived food environment domains (food availability, accessibility, affordability, and advertising) were calculated by averaging relevant items. The associations between perceptions of the community food environment, dietary behavior, and food security were examined using linear regression analyses adjusting for individual sociodemographic characteristics and regional-level socioeconomic indicator. Of the 666 respondents who completed the household food security survey module, 255 (38.3%) experienced food insecurity (comprising 7.8% marginal, 18.8% moderate, and 11.7% severe food insecurity). In adjusted models, food-insecure respondents reported significantly less favourable perceptions of their local food environment compared to food-secure respondents. Specifically, they expressed greater disagreement with statements about the overall food environment (Mean Difference (MD)=0.38; 95%CI (0.25,0.51)), availability of healthy food outlets (MD=0.29; (0.15, 0.43)), accessibility of healthy food outlets (MD= 0.48; (0.28, 0.68)), and affordability of healthy food (MD=0.60; (0.38, 0.83)), but no differences in perceptions of unhealthy food advertising. Food-insecure respondents also reported poorer dietary behaviours – on average rating their overall diet quality lower (MD=0.33; (0.15, 0.50)), consuming more servings of sugar-sweetened beverages (MD=0.18/day; (0.01, 0.35)), and less vegetable servings (MD=-0.32/day; (-0.61, -0.03)) than food secure respondents. This study highlights the link between perceived community food environments, food insecurity, and dietary behaviours in regional Australia. Food-insecure individuals reported poorer perceptions of food availability, access, and affordability, which were associated with lower diet quality and less favourable dietary behaviours. These findings underscore the need for public health interventions that address both structural and perceived barriers to healthy food access.