To provide an inspecting method and a manufacturing method of a ball grid array device (referred to as BGAD hereinafter) using a mounting device capable of putting in/out the BGAD to be subjected to a burn-in test from a test socket without damage.

The mounting device of the BGAD includes a base member, a plurality of long and narrow contact members fixed to the base member and having an interconnecting end at one of longitudinal sides and a free end at the other side in a shape of applying a laterally downward pressure to a terminal ball of the BGAD by contact from a lateral side, and moving members 28 and 50 for opening/closing the free ends of the contact members for causing the free end of the contact member to come farther away from or into contact with the terminal ball of the BGAD. The BGAD is mounted on the mounting device which is structured to cause the free end of the contact member to come into contact from the lateral side to apply the laterally downward pressure to the terminal ball of the BGAD, and the BGAD is electrically connected with the exterior via the terminal ball and the contact member for inspection.