Guava leaves (Psidium guajava) offer great potential as a natural resource for both cosmetics and traditional remedies. Herbal formulations are now widely utilized for their therapeutic benefits, as medicinal plants and their active compounds are generally less toxic and cause minimal side effects. This review focuses on the bioactive compounds found in guava leaves, including flavonoids, tannins, saponins, and triterpenoids, which contribute to their antioxidant, anti-inflammatory, and antimicrobial properties. These attributes support therapeutic activities such as wound healing, eczema treatment, and hair care. Cosmeceutical formulations incorporating guava leaves offer a natural and effective alternative to synthetic agents, enhancing product safety, efficacy, and sustainability. Guava leaf extracts are effective in promoting hydration, anti-aging, and skin- brightening benefits for both skin and hair. Guava leaves' special therapeutic and cosmetic qualities are used in products like cleansers, moisturizers, and serums that appeal to diverse skin types. Specific benefits, including antioxidant richness, cost-effectiveness, and targeted therapeutic effects, further strengthen the case for their sustainability. Additionally, combining guava leaves with synthetic ingredients in cosmetics can amplify their benefits. This review also discusses the ways that guava leaves support skin health, reduce oxidative stress, and inhibit microbial growth, offering valuable insights for future product development and clinical applications.