Fennel (Foeniculum vulgare Mill.), belonging to the Apiaceae (syn. Umbelliferae) family, is a well-known medicinal, aromatic, and vegetable plant widely used as a traditional spice throughout the world, and based on scientific evaluation and traditional applications, it remains one of the most commonly used herbal plants, having been employed in the treatment of over forty different kinds of illnesses. A comparison of pure fennel (Foeniculum vulgare) fruits with branded fennel powder was carried out based on morphological, phytochemical, and physicochemical parameters. Phytochemical constituents of the fennel extracts were analyzed by chemical tests and thin-layer chromatography, which revealed the presence of flavonoids, terpenoids, and glycosides. Phytochemical studies have revealed beneficial ingredients, including phenolic compounds, flavonoids, volatile compounds, fatty acids, and amino acids. The physicochemical parameters were evaluated using ash value, moisture content, extractive value, swelling index, and foaming index, which resulted in minor differences between the branded and pure Feniculum vulgare. It is concluded that adulterants are added to branded fennel, but within harmful limits. The branded fennel powder was found satisfactory.