Abstract Background Health inequalities partially remain due to differences in diet between socioeconomic groups. Examining the association between socio-ecological factors and the diet of socioeconomically disadvantaged (SED) individuals can enhance the development of interventions to decrease health inequalities. Methods In total, 278 SED adults residing in two Flemish municipalities completed a survey addressing sociodemographics, diet, health and their perceptions of the food environment. The objective food environment was examined by assessing food retailer information in street network-based buffers of 500m and 1000m around participants’ addresses. Linear regression was used to test assumptions. Results Individual factors such as poor subjective health (OR0.58;CI 0.34-0.97), food insecurity (OR0.60;CI 0.38-0.94) and living alone (OR0.86;CI 0.75-0.98) were negatively associated with healthy dietary habits such as daily fruit and vegetable (FV) consumption. Positive perceptions on the availability of FV were positively associated (OR1.09;CI 1.02-1.17) with daily FV consumption. Objective food environmental factors showed a stronger association with unhealthy dietary habits. A greater amount of retailers within 1000m walking distance was negatively associated with fast-food (OR0.96;CI 0.94-0.99) and sugar-sweetened beverages (SSB) consumption (OR0.93; CI 0.88-0.98). More supermarkets within 500m distance was negatively associated (OR0.77;CI 0.58-0.97) with SSB consumption, while more convenience stores within a 1000m distance was positively associated (OR1.48;CI 1.17-1.88) with SSB consumption. Conclusions Our findings suggest that factors associated with the diet of SED adults differ according to food and drink items. Interventions focused on this population should take these differences into account. Key messages Individual and food environmental factors are both associated with the diet of socioeconomically disadvantaged adults but differ according to food and drink items. Individual factors and ...