The present study focuses on the formulation and evaluation of a polyherbal powder shampoo using traditionally recognized Ayurvedic medicinal plants for effective and eco-friendly hair care. The formulation incorporated Acacia concinna (Shikakai), Sapindus mukorossi (Reetha), Emblica officinalis (Amla), Eclipta alba (Bhringraj), Azadirachta indica (Neem), Hibiscus rosa-sinensis (Hibiscus), and Multani Mitti, selected for their cleansing, conditioning, antimicrobial, antioxidant, and hair growth–promoting properties. Herbal ingredients were collected, authenticated, shade-dried, pulverized, and sieved to obtain uniform powders suitable for formulation. Three formulations (F1, F2, and F3) were prepared by varying the proportions of active ingredients and evaluated systematically. Preliminary phytochemical screening confirmed the presence of saponins, flavonoids, tannins, alkaloids, glycosides, phenolics, proteins, and mucilage, which contribute to the therapeutic efficacy of the formulation. Organoleptic evaluation demonstrated acceptable colour, odour, texture, and appearance, while physicochemical studies indicated suitable pH, low moisture content, and good flow properties. Functional performance tests revealed satisfactory foaming ability, cleansing efficiency, conditioning effect, and wetting time. Antimicrobial and anti-dandruff studies showed significant inhibitory activity against Malassezia furfur and selected bacterial strains. Among the developed formulations, batch F3 exhibited superior overall performance due to its balanced cleansing, conditioning, and scalp-protective properties. The study concludes that the developed polyherbal powder shampoo represents a safe, stable, biodegradable, and effective alternative to synthetic shampoos. The formulation successfully integrates traditional Ayurvedic knowledge with modern scientific evaluation, thereby supporting the growing demand for sustainable and herbal cosmetic products.