PURPOSE: A board for mounting a semiconductor package is provided to prevent a void phenomenon by forming an air vent line in a mounting area for mounting the package with a cross structure. CONSTITUTION: A package exposing a lower side of a chip mounting plate is mounted in a board(10). An additional air vent line(22) is formed in a mounting area(12) of the board adhered by a solder paste. The air vent line is formed in an adjacent part of a plurality of thermal through vias(14) formed in the mounting area. The air vent line is formed with the cross structure of a width vent line(22a) and a length vent line(22b) which cross the plurality of thermal throw vias in the mounting area.
