Silybum marianum L., commonly known as milk thistle, is traditionally recognized for its hepatoprotective properties. This is primarily due to silymarin, a mixture of flavonolignans with strong antioxidant and anti-inflammatory activities. Although many studies have reported on its biological activities, critical syntheses that compare extraction technologies and highlight its protective roles beyond liver health remain limited. Despite the abundant literature, the protective effects of milk thistle against skin damage remain largely unexplored. To address this gap, we performed a comprehensive literature search across PubMed, Scopus, Web of Science, and Google Scholar. Our research covered publications up to February 2025 and used predefined keywords, including extraction methods for the release of silymarin, in vitro, in vivo, and clinical studies relevant to its protective effects against skin damage. The evidence indicates that silymarin exerts protective effects on the skin, including the prevention of photoaging, the management of acne, the promotion of wound healing, and the defense against UV-induced damage, through the activation of Nrf2 and the preservation of the extracellular matrix. These results highlight the promising dermatological benefits of silymarin, as well as the need for further clinical studies and the optimization of environmentally sustainable extraction techniques for large-scale production.