Mild tricuspid insufficiency is a condition in which blood from the right ventricle flows back into the right atrium during systole through the incompletely closed tricuspid valve. The tricuspid valve is the valve between the right atrium and the right ventricle of the heart. It is called the tricuspid valve because it is made up of three valves, which act as “one-way valves” to ensure that blood can only enter the right ventricle from the right atrium and that a certain amount of flow is guaranteed. Tricuspid insufficiency is a condition in which the tricuspid valve fails to close completely and some of the blood from the right ventricle refluxes back into the right atrium during systole. The degree of tricuspid valve closure insufficiency is mostly estimated by echocardiography, and the regurgitant bundles are smaller, narrower, and centered, and the regurgitation is slower. Mild tricuspid valve closure insufficiency is mostly caused by physiologic reasons in the normal population, and may have no hemodynamic abnormality and no obvious symptoms; it may also be caused by pulmonary hypertension, pulmonary heart disease, rheumatic tricuspid valve lesions, and other etiologies. It is recommended to consult a specialist and follow the doctor’s instructions for further examination and treatment.