Background: Rumex crispus L., commonly called as "yellow dock" in English, "patience frisee" in French, and "Ampfer" in German, and ′aceda de culebra′ in Spanish is a well-known herb belonging to Polygonaceae. Roots of the herb are used as medicine in homoeopathy. Objective: The pharmacognostic and physicochemical studies on roots have been carried out to enable the use of correct species and standardize the raw material. Materials and Methods: Pharmacognostic studies on roots of authentic raw drug have been carried out; physicochemical parameters, namely, extractive value, ash values, formulation besides weight per mL, total solids, alcohol content along with high-performance thin layer chromatography (HPTLC) and ultraviolet studies for mother tincture have been worked out. Results: Roots are blackish-brown, wiry, rounded with irregular striations, tortuous; internally, it is softwood, light-yellow, and fracture fibrous. Phellem is 8-10 layered, discontinuous, and tanniniferous. Phellogen is two-layered and contains inulin crystals in few. Outer phelloderm is 12-16 layered often containing spherocrystals and associated with stone cells. Secondary phloem is up to 25 layered. Xylem is in the form of strips. The physicochemical properties and HPTLC values of the drug are standardized and presented. Conclusion: The powder microscopic features and organoleptic characters along with anatomical and physicochemical studies are diagnostic to establish standards for the drug.