There is no authoritative information on the causes of high blood pressure after stem cell transplantation, and it is generally believed to be related to transplantation rejection or induced hypertension. 1. Transplantation rejection reaction: this disease mainly causes loss of graft function after producing immune response against transplantation antigen, or causes damage to the recipient’s organism, which may be related to factors such as mismatch of blood type, allergy to human leukocyte antigen, and viral infection, etc. Patients will have mild hypoplasia of plant function. Patients will experience mild or severe hypoplasia of the grafts, and common symptoms include fever, abnormal blood pressure, swelling and pain in the inhibited area, while some patients will experience elevated blood pressure. 2. Hypertension: the etiology of this disease is not clear. High blood pressure after stem cell transplantation may be due to the fact that the patient suffers from high blood pressure, which is induced by the use of other drugs during the suppression process or the patient is in a state of prolonged mental tension, resulting in high blood pressure, and headache, cardiac arrhythmia, tinnitus and other symptoms may occur. It is recommended that patients with high blood pressure after stem cell transplantation actively cooperate with the doctor’s treatment to clarify the specific causes.