The invention discloses application of fructus chaenomelis betulinic acid in preparing a medicine for resisting hypertensive myocardial fibrosis, and belongs to the technical field of biological medicines. The fructus chaenomelis betulinic acid is applied to treat treating spontaneously hypertensive rats (SHR), and the result shows that after drug administration treatment for 12 weeks, blood pressure of each group of SHR is reduced, and serum endothelin (ET) contents of each dosage group of fructus chaenomelis betulinic acid and a captopril CAP group are remarkably reduced; the nitric oxide (NO) content is remarkably improved; according to each dosage group of fructus chaenomelis betulinic acid, the contents of MCP-1, TNF-alpha, IL-1, IL-6, CRP and MDA can be reduced, so that the result shows that the fructus chaenomelis betulinic acid can be beneficial to reducing of the content of cardiac muscle tissue inflammatory factors, reducing of damage of oxidative stress on tissues, improvingof tissue oxidation resistance, and improving of myocardial fibrosis through multiple target points.