Sea buckthorn proteins and peptides have received increasing attention as functional ingredients in food and pharmaceuticals due to their potential health benefits, for example, antioxidant and immunomodulatory activities. Various methods, including aqueous extraction, enzymatic hydrolysis, and membrane separation, have been used to extract these bioactive compounds from plants. This chapter summarizes and organizes the extraction methods of sea buckthorn proteins and peptides and compares their efficiency, yield, and quality. Additionally, this chapter analyzes the reported biological activities of sea buckthorn proteins and peptides, including their antioxidant, anti-inflammatory, and immunomodulatory activities, which are attributed to their mechanisms of action on human health. Finally, this chapter identifies gaps and limitations in current research on sea buckthorn proteins and peptides, such as the lack of human clinical trials and standardization of extraction and analysis methods. Future research should focus on conducting well-designed human clinical trials and standardizing extraction and analytical methods and establish their potential applications in food and medicine.