The utility model relates to a cover, and discloses a cup cover with quick locking function, and a cup, wherein the cup cover includes a cover body and a rotating member arranged on the cover body, the rotating member is provided with a clamping hook, and the rotating member can rotate relative to the cover body, so as to drive the clamping hook to reciprocate between a first position and a second position. A rotatable clamping buckle locking structure is used in the utility model to replace a screw thread locking structure in the related art, which can reduce the time for operating the cup cover, implements quick opening and closing of the cup cover, enables the drinking action of a user more smooth and nature, and helps to improve the user experience.