A semiconductor package including an interposer substrate, first to third semiconductor chips on the interposer substrate to face each other, an underfill part between each of the first to third semiconductor chips and the interposer substrate, a first side-fill part extending upward from a lower end of side walls of the first to third semiconductor chips, and a second side-fill part between the side walls of the first to third semiconductor chips and extending from the first side-fill part to an upper end of the side walls of the first to third semiconductor chips may be provided.