1 Natural Biomaterial Composites for Tissue Engineering: Challenges and Opportunities 1 Tissue engineering has appeared as a promising frontier in regenerative medicine, aiming to restore, maintain, or improve tissue functions. Central to this field are natural biomaterialssubstances derived from nature that offer biocompatibility and functional mimicry of the body's own tissues. These materials, when combined into composites, hold incredible potential for producing scaffolds that support cell growth and tissue regeneration.This review explores the promising role of natural biomaterial composites in tissue engineering, highlighting their potential to improve regenerative therapies. We begin by discussing the fundamental importance of tissue engineering and the unique advantages offered by natural biomaterials such as collagen, gelatin, and decellularized extracellular matrices. The paper then examines various fabrication techniques, including 3D bioprinting and electrospinning, which enable the creation of complex, functional scaffolds. Emphasis is placed on the biocompatibility and mechanical properties of these composites, critical factors influencing their success in vivo. Additionally, we explore their diverse applications in regenerating skin, bone, and cartilage, showcasing their versatility. Lastly, the review considers future trends and ongoing challenges, aiming to guide the development of innovative, effective, and safe biomaterial-based solutions for tissue regeneration. 1 6 Ali Shirbacheh Service d’urgence, Centre Hospitalier de l'agglomération de Nevers France shirbacheali@gmail.com kimiya shirbacheh Department of Cellular and Molecular Biology, Islamic Azad University, Najafabad Branch, Isfahan Iran kimiyashirbacheh@gmail.com Kamran Shirbache Hôpital Robert Debré, Groupe Hospitalier Universitaire AP-HP Nord-Université Paris-Cité, Paris France Shirbache.k@ght.fr Mojtaba Karbalaee Shoushtar Faculty of Medical Sciences, Shoushtar Iran mehdikarbalaee99@gmail.com Tissue Engineering Biomaterials 3D Bioprinting Electrospinning [1] A. Chandrasekharan, E. Yazdani, A. Mahdian, S.A.S. Marnani, S. Askari, Ocular regenerative medicine using decellularized tissues, Journal of Composites and Compounds 4(11) (2022) 97-108.##[2] A. Shafiee, A. 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