Functional tricuspid valve regurgitation (TR) is often secondary to left-sided valvular heart diseases. The precise diagnosis of TR degree and reasonable treatment can improve the long-term prognosis of patient. Now we believe that rectifying the TR during left cardiac valve surgery can prevent a further development of TR and avoid the reducing of the cardiac function for patients with moderate TR, tricuspid valve annulus diameter>40 mm in late diastole, tricuspid valve diameter/body surface area>21 mm/m2, and intraoperative tricuspid valve diameter >70 mm, especially for patients with atrial fibrillation and atrial enlargement. The use of prosthetic ring can effectively prevent recurrence of TR in long term and we should try to use hard or semihard "C" shape prosthetic ring as much as possible. The tricuspid valve replacement should be avioded because of its higher mortality.