A semiconductor package includes a first semiconductor chip, a second semiconductor chip, first main connection pad structures, and first dummy connection pad structures. The first main connection pad structures are arranged at an interface between the first semiconductor chip and the second semiconductor chip and arranged to be apart from each other by a first main pitch in a first direction parallel to a top surface of the first semiconductor chip, wherein each of the first main connection pad structures includes a first connection pad electrically connected to the first semiconductor chip, and a second connection pad electrically connected to the second semiconductor chip and contacting the first connection pad. The first dummy connection pad structures are arranged at an interface between the first semiconductor chip and the second semiconductor chip, are arranged to be apart from the first main connection pad structures, and are arranged to be apart from each other by a first dummy pitch in the first direction, the first dummy pitch being greater than the first main pitch.