A semiconductor package is provided. The semiconductor package includes a first package comprising a first substrate and a first semiconductor chip, a second package arranged on the first package, and the second package comprising a second substrate and a second semiconductor chip, a first solder ball and a supporter layer arranged between the first package and the second package, and a dam arranged between the first package and the second package, the dam being in contact with a sidewall of the supporter layer, and the dam completely surrounding the sidewall of the supporter layer.