Provided is a seal bead structure of a gasket capable of reducing the reactive force generated in a common bead portion provided between multiple through-holes and thereby capable of achieving a stable sealing function by means of aligning the compression property over the entire bead. In order to achieve this, two through-holes are provided in a row in the flat portion of a metal gasket, with one seal bead provided on the edge of one through-hole, the other seal bead provided on the edge of the other through-hole, and a common bead portion for the both seal beads provided in the intermediate position between the both through-holes, the common bead portion having a two-stage half bead shape in which the half beads are formed on two stage in the same direction.