A semiconductor device connection structure includes: a semiconductor element having a plate shape and including an external connection electrode on a surface of the semiconductor element a support member which is stacked on the semiconductor element to be adhered to the semiconductor element and of which adhesion surface has a column shape that is substantially same as that of the semiconductor element, a thickness of the support member in a stacking direction being larger than that of the semiconductor element and a flexible board configured to be electrically connected to the external connection electrode. The flexible board is arranged on a side surface of the semiconductor element and on a side surface of the support member and is adhered only to the side surface of the support member with an adhesive.
