Provided is a semiconductor device connection structure capable of improving adhesion strength without influencing performance of a semiconductor element by a simple method. The semiconductor device connection structure according to the invention includes a silicon substrate having a plate shape and including an external connection electrode on a surface thereof a support member which is adhered to a rear surface of the silicon substrate and of which adhesion surface has a column shape that is substantially same as that of the silicon substrate, a thickness of the support member being larger than that of the silicon substrate and a flexible board having an inner lead therein configured to be connected to the external connection electrode. The flexible board is arranged on a side surface of the silicon substrate and is adhered to the support member with an adhesive.
