The purpose of this paper is to verify the knowledge that is useful for legume producers in relation to consumers’ eating habits in the field of legume products. According to experts, leguminous products have a positive effect on human health. The tendency towards healthy eating habits is also associated with the idea of sustainable consumption. The authors have attempted to combine these two trends. The main goal was to determine, among consumers, the level of knowledge about legumes, product purchase motives, and preferred places of purchase. This study was carried out with the use of an authorial questionnaire. In total, 1067 respondents from all regions of Poland participated in the study. The Statistica 13.1PL programme was used for statistical analyses. Methods used: descriptive statistics, discriminant analysis and linear regression analysis. With the aid of the conducted analyses, it was possible to determine that peas, beans, soybeans and lentils are the most recognised and most frequently consumed products (in various configurations) among the residents of the studied groups. The most important motives for their purchase among the surveyed consumers were “flavour”, “price” and the fact that these products can be an alternative to meat products and contain a lot of protein and fibre. The purchase channels that legume product producers must pay attention to are large-area shops and online sales. Sustainable consumption awareness for the consumers of legume products is best defined by a variable in the regression equation—“no harmful substances used during its production”. The legume products market has not yet flourished in Poland. The products are an excellent alternative to meat products due to their high protein content. Pro-health education has a measurable effect and consumer awareness is growing. Producers should use this knowledge by emphasising, in the promotion of products, that the products are produced in accordance with the idea of sustainable development, without the use of harmful substances, and that no means are used to extend the shelf life