Gasket

A gasket sandwiched between a cylinder head and a cylinder block and sharing, with the cylinder block, a combustion chamber hole extending in a hole axis direction, the gasket comprising:

• a first plate portion abutting against the cylinder head and having a substantially constant plate thickness;
• a second plate portion abutting against the cylinder block and having a substantially constant plate thickness;
• an intermediate plate portion sandwiched between the first plate portion and the second plate portion and having a substantially constant plate thickness;
• and
• a shim sandwiched between the first plate portion and the intermediate plate portion and disposed over an entire periphery of a peripheral edge of the combustion chamber hole, wherein
• the shim includes a gradually changing portion with a thickness in the hole axis direction that becomes thicker with a separation from the peripheral edge of the combustion chamber hole, wherein
• the shim further includes a round edge portion that is provided on an end of the shim on an opposite side to the peripheral edge side of the combustion chamber hole, and
• a surface of the gradually changing portion and a surface of the round edge portion on the cylinder head side are both smooth and joined continuously to each other.