This review aims to evaluate the cosmetic and exfoliating properties of Linum usitatissimum L. (flaxseed) and to highlight its potential as a natural, sustainable skincare ingredient. A comprehensive literature review was conducted using scientific databases to collect data on the phytochemistry, mechanisms of action, cosmetic formulations, and exfoliating properties of flaxseed. The study analyzed bioactive components such as alpha-linolenic acid, lignans, mucilage, and phenolic compounds for their dermatological relevance. Additionally, evidence from in vitro, ex vivo, and limited clinical studies was critically assessed to understand flaxseed’s multifunctional role in hydration, anti-aging, and exfoliation. Flaxseed oil demonstrated significant anti-inflammatory and antioxidant properties due to its rich content of omega-3 fatty acids and lignans. Mucilage polysaccharides showed strong film-forming and moisturizing abilities, enhancing skin hydration and barrier function. Ground flaxseed particles served as effective, biodegradable exfoliants, while mucilage-based systems promoted gentle enzymatic desquamation. The combination of these effects supports skin smoothness, elasticity, and rejuvenation. However, formulation stability, standardization of bioactives, and variability in extraction processes remain key challenges that need further optimization. Flaxseed is a promising botanical for cosmetic use, offering biocompatible, eco-friendly, and multifunctional benefits. Continued research and standardization can establish flaxseed as a reliable natural alternative to synthetic cosmetic agents in modern skincare formulations.