A semiconductor device or semiconductor device package for transmitting a plurality of differential signals, the reliability of which hardly deteriorates. The semiconductor device is an area array semiconductor device in which a plurality of lands (external terminals) including a plurality of lands for transmitting a plurality of differential signals are arrayed in a matrix pattern in the back surface of a wiring substrate. Some of the lands are located in the outermost periphery of the matrix pattern. Some others of the lands are located inward of the outermost periphery of the matrix pattern and in rows next to the outermost periphery. The spacing between lands in a second region between the lands located in the rows next to the outermost periphery and the side surface of the wiring substrate is larger than in a first region in the outermost periphery.