Abstract: An easily openable can lid wherein buckling parts are provided nearby a peripheral groove formed on the can lid in a range of 25 to 65 degrees from the center of the top plate from a line between the tip end of the openable member and the center of the top plate in all sector segments formed when the can lid is divided into four sector segments by a line between an extreme end of the openable member and the center of the top plate and a line which passes through the center of the top plate and orthogonally intersects the above described line. A reinforcing part with a reinforcing effect smaller than a buckling effect is provided at a coupling part between the top plate and the peripheral groove or near said coupling part except for the buckling part at an opposite side of the openable member and its neighborhood to provide a difference of strength between the buckling part at the openable member side and the buckling part at an opposite side of the openable member.