A locking mechanism for container and lid thereof may include a container and a lid, and the peripheral edge of the upper opening of the container has a first periphery edge. At least two first coupling portions, which are located at symmetric positions, and at least two second coupling portions, which are located at symmetric positions, outwardly protrude from the first periphery edge respectively. The lid comprises a second peripheral edge at the outer periphery thereof, and the inner surface of the second peripheral edge is configured to couple with and cover the first peripheral edge of the container. At least two first connecting portions respectively protrude from the second peripheral edge at symmetric positions, and at least two second connecting portions, which are located at symmetric positions, outwardly protrude from the second periphery edge respectively.