The press cake obtained after the production of flaxseed oil is a nutritionally valuable product distinguished by its high protein and fiber content. It is known that this fraction remaining after cold-pressing contains approximately 30-40% protein, while also carrying a significant amount of dietary fiber and carbohydrates. The high protein content and balanced amino acid profile make flaxseed press cake a strong source of plant-based protein; this characteristic supports the product’s use both as an alternative protein source in animal nutrition and as a functional ingredient in food formulations when appropriately processed. Especially, the high fiber content and natural polysaccharide structure contribute to this material exhibiting water-holding capacity and emulsifying properties. These properties increase the usage potential of flaxseed press cake in bakery products and functional food applications. Furthermore, flaxseed press cake offers a nutritionally and functionally valuable component profile due to its content of lignans, phenolic compounds, and minerals. With these characteristics, flaxseed press cake stands out as a high-nutrient and value-added raw material that can be evaluated in feed and food applications.