SEAL STRUCTURE

PROBLEM TO BE SOLVED: To ensure sealability over the full length in a seal longitudinal direction even when an elastic seal member has an end part in the intermediate location between continuously joining-surfaces of two members with each other.SOLUTION: A seal structure is provided for sealing a joint part of a cylinder head 1 and a cylinder head cover 2 by interposing in the joint part, an elastic seal member 11 having an end part in the intermediate location of the joining-surfaces where the cylinder head 1 and the cylinder head cover 2 are continuous with each other. A seal groove 16 formed in the cylinder head cover 2 has a widened groove end portion 18 which is widened in a seal width direction in one end in the seal longitudinal direction. The elastic seal member 11 has a widened seal portion 13 which is mounted in the widened groove end portion 18 at a gap 20 to the lateral side of thereof and widened in the seal width direction, and a first protruding portion 14 which is protruded from the lateral side at one end side in the widened seal portion 13 in the seal longitudinal direction and comes in press-contact with the lateral side of the widened end portion 18 while the cylinder head 1 and the cylinder head cover 2 are joined together.