There is no difference between Juniperus chinensis and Psidium guajava, they are the same kind of plant and belong to a kind of traditional Chinese medicine with sweet taste, slightly bitter and cold nature. According to Chinese medicine, Guahuaguo bark can play the role of clearing heat and resolving phlegm, relieving qi and broadening chest; Guahuaguo seeds have the function of moistening lung and resolving phlegm, laxative and laxative; Guahuaguo tuberous root is often called smallpox powder, which has the function of clearing heat and fire, generating body fluid and quenching thirst, eliminating swelling and draining pus. Psidium guajava can be combined with substances such as Chuanbei and Lily to make Beiling Cough Soup, which can be applied to relieve the symptoms of bronchitis; Psidium guajava can be combined with fire hemp kernel, cypress kernel and peach kernel to make drugs, which have positive significance in the treatment of constipation; Psidium guajava injection can also be used to assist in the treatment of coronary heart disease. From the perspective of western medicine, fatty alcohols, fatty acids, glucosides, spinach sterols, amino acids and alkaloid-like substances that can be isolated from Psidium guajava can be used in clinical practice. In addition to the above, Guahu is also available as food, but it should be noted that Guahu is an herbal medicine and should not be consumed in excess in daily life, and should be used as a medicinal herb in accordance with medical advice.