Plants being rich sources of phytochemicals behave as therapeutic agents and also provide a variety of natural dyes for applications in the textile, cosmetic, and pharmaceutical industries. In recent decades, plant-based natural colorants have gained increasing importance due to their non-toxic, eco-friendly, therapeutic, and sustainable characteristics. Thus, plant-based natural colorants meet the sustainable development goal which is related to the good health and well-being. Medicinal plants have been investigated for their therapeutic properties to find their applications in skin- and hair-care cosmetics. Natural hair colors have been used to dye gray hairs to replace synthetic hair dyes. Recently, formulations have been developed to apply natural colorants in multipurpose lip-care cosmetics. Due to their different chemical structures and compositions, natural colorants require various extraction methodologies to obtain greater yield and maintain their chemical integrity. For skincare applications, the study of therapeutic properties and cytotoxicity of extracts of natural dyes is essential. Antimicrobial, antioxidant, anti-inflammatory, anti-cancer, cytotoxicity, and anti-aging potential of natural colorants provide additional benefits for producing multifunctional skincare cosmetics. Natural colorants can be extracted from plant wastes such as fruit and vegetable peels; therefore, they meet the sustainable development goals of good health and well-being and also ensure the sustainable consumption and production of cosmetic products employing natural plant waste products. In this chapter, we will provide a detailed overview of plant-based natural colorants, chemistry, extraction methods, and therapeutic properties for their application in cosmetic industry.