Disclosed is a container lid for vacuum sealing which generates negative pressure in the internal space of a container, which is provided by covering the open upper part of a container main body, and seals same. An annular packing is mounted so as to go around the inner surface of a lid main body, and a check valve is mounted in the inner part of the outer surface of the lid main body. The check valve generates negative pressure in the internal space of the container by allowing air inside the container to flow to the outside but preventing outside air from flowing into the container when a pressure difference occurs between the inside and outside of the container. A plurality of self catching protrusions are provided respectively at a plurality of points on the edges of the lid main body, and a plurality of locking members are mounted respectively and pivotably in sections adjacent to the plurality of self catching protrusions. Each locking member comprises: self-locking protrusions which are press-fitted and coupled to the self catching protrusions in a closed state so that the locking members are not released； and main body-locking protrusions which prevent the container lid from being taken off from the container main body by being caught by the circumference of the opening part of the container main body or a main body catching protrusion, even if the container lid rises due to the expansion of the packing as a result of a decrease in the negative pressure generated inside the container.
