BACKGROUND: Robotic cardiac surgery, unlike minimally invasive surgery, requires the assistance of a bedside surgeon to complete the procedure. Console surgeons alone cannot manipulate the surgical field effectively, particularly during subvalvular procedures and mitral annuloplasty near the medial left atrium (LA). METHODS: We have developed a novel reusable retractor with a self-adjustable system that facilitates clear visualization of the subvalvular apparatus or annulus. The feature of this retractor is the unique slit at the end of the plate. By passing the other end from the outside to the inside, the slit transforms into a circular opening. RESULTS: SInce the plate can extend into the left ventricle, it provides a better view of the posteromedial papillary muscle. Moreover, the auto-adjustment function allows excellent exposure of the entire LA, particularly the medial mitral annulus.CONCLUSIONS: Our self-adjustable retractable plate offers a versatile solution for obtaining clear views of the subvalvular tissue, mitral annulusduring robotic cardiac surgery.