Seaweeds are a valuable resource for food development due to their nutritional composition and technological properties. This work aimed to evaluate Undaria sp. powder (UP) properties and its performance as a functional ingredient in low-fat pork burgers. UP proximal composition, physicochemical, and functional properties were evaluated. UP showed a monomodal particle size distribution, low moisture, and low water activity. It showed both high mineral (26.5 g/100 g db) and total dietary fiber (40.685 g/100 g db) contents. UP lipid level was low (5.2 g/100 g db). The fatty acid profile presented high proportions of SFA and MUFA (48.8 % and 38.2 %, respectively), followed by PUFA (13 %), with palmitic (C16:0; 36.9 %) and oleic acids (C18:1n-9; 34.4 %) in the highest abundance. Concerning UP properties, it retained more water than lipids; its total phenolic content reached 15.50 mg GAE/g, and the antioxidant capacity was 29.42 and 34.50 mu mol TE/g for DPPH and ABTS methods, respectively. Burgers were manufactured with UP or milk protein concentrate (MPC) as emulsifiers, packaged, and stored frozen. Formulation and storage time effects on the product's physicochemical and techno-functional properties were evaluated. The UP addition to burgers increased yields, hardness, and chewiness, while reduced shrinkages in comparison with control burgers with MPC. Although the color was adversely affected by the formulation, it was balanced with carmine addition. Even though the UP burgers showed higher antioxidant capacity, lipid oxidation increased during storage and with UP incorporation. UP addition did not affect the product's fatty acid profiles or fat contents. Therefore, UP could be an adequate strategy for developing meat products with improved techno-functional and antioxidant properties.