A sealing ring protection sheet for a trocar of the present invention includes a positioning skirt, a support piece and a curved protection sheet. An upper end of the support piece is connected to an inner side of the positioning skirt, and a lower end of the support piece is connected to an upper end of the curved protection sheet. The curved protection sheet is of a curved and asymmetrical sheet-like structure, forming an easily deformable region and a protection region along two sides of a center line and its extension line of the positioning skirt separately. A left side and a right side of the curved protection sheet have different curvatures. The design of different curvatures of the left and right sides reduces resistance forces when various special-shaped instruments are inserted and removed. An end sealing assembly and the trocar of the present invention include the sealing ring protection sheet for a trocar of the present invention, capable of not only ensuring that a funnel-shaped sealing ring is not punctured by a surgical instrument in a surgical process, thereby ensuring a good sealing performance, but also reducing a moving resistance force, and particularly reducing a resistance force when various special-shaped surgical instruments are inserted and removed.
