Burdock and yam are two completely different plants, there is an essential difference, mainly in the species, flavor, parts of the medicine and different functions. 1. Genus: burdock originated in China, also known as Oriental ginseng, belongs to the Asteraceae burdock-type plants; and yam is the dried rhizome of the plant Dioscorea, also known as Dioscorea, yam. 2. Different tastes: burdock is cool, bitter and slightly sweet, while yam is flat and sweet. 3. The medicinal parts: burdock medicinal parts include the fruit and rhizome, the fruit is also known as burdock seed, the efficacy of the two are different; and yam to the rhizome into medicine. 4. Functions: Burdock root has the effect of clearing heat and removing toxins (removing heat and toxins from the body), dispersing wind and facilitating the pharynx, and is mainly used for the treatment of wind-heat colds, coughs, sore throats, boils, tinea pedis, eczema and other diseases; Burdock seed has the effect of promoting lungs to dispel rashes, dispersing wind-heat and facilitating the pharynx to resolve toxins, and is mainly used for the treatment of coughs and sputum, wind-heat colds, rubella, measles, mumps and sore throats, and other diseases. Yam has a tonic lung thirst, spleen and stomach, benefit the essence of the kidney and other effects, mainly used for the treatment of spleen deficiency, less food, loose stools (feces thin and not shaped) diarrhea, lung deficiency, cough, kidney deficiency, spermatorrhea, with frequent urination and other diseases. To summarize, the difference between the two mainly include the above four aspects, due to the efficacy of the two main treatment is different, the specific use of which drug, need to be guided by a professional doctor to use, can not be blindly self-selected.