Provided are a semiconductor device and a method of fabricating the same, and more particularly, a semiconductor package and a method of fabricating the semiconductor package. The semiconductor package includes a first package that comprises a first substrate, at least one first semiconductor chip stacked on the first substrate, and first conductive pads exposed on a top surface of the first substrate; a second package disposed below the first package such that the second package comprises a second substrate, at least one second semiconductor chip, and second conductive pads exposed on a bottom surface of the second substrate; and a connection unit that extends from the first conductive pads to the second conductive pads such that the connection unit covers a side surface of the first package and a side surface of the second package in order to electrically connect the first package to the second package.