PROBLEM TO BE SOLVED: To provide a mounting structure having a configuration to attach a relay board to a master board by way of a board-to-board connector, which configuration allows shielding of electromagnetic noises and overcoming of fitting failures of the board-to-board connector, without increasing the size of the relay board.SOLUTION: A mounting structure for an electronic endoscope apparatus having an electronic scope and a processor, comprises: a sheath inserted into a flexible tube of the electronic scope; a plurality of cables which are inserted into the sheath and one ends of which are each connected to an imaging element of the electronic scope; a relay board to which the other ends of the plurality of cables, drawn out from an end portion of the sheath, are connected; a master board connected removably by the relay board and the connectors; and a conductive shield case covering at least a portion of the master board. In this configuration, the sheath includes a conductive shield member into which the plurality of cables can be inserted, and the shield member is electrically connected to the shield case at an end portion of the sheath.SELECTED DRAWING: Figure 4【課題】中継基板を親基板に基板対基板コネクタを用いて取り付ける構成において、中継基板を大型化することなく、電磁ノイズを遮蔽すると共に、基板対基板コネクタの嵌合不具合を解消可能な実装構造を提供する。【解決手段】電子スコープとプロセッサとを有する電子内視鏡装置用の実装構造を、電子スコープの可撓管内に通されたシースと、シースに挿通され、一端が夫々電子スコープの撮像素子と接続された複数のケーブルと、シースの端部から引き出された複数のケーブルの各他端が取り付けられた中継基板と、中継基板とコネクタによって着脱可能に接続される親基板と、親基板の少なくとも一部を覆う導電性のシールドケースと、から構成する。この構成において、シースは、複数のケーブルを挿通可能な導電性のシールド部材を有し、シースの端部において、シールド部材は、シールドケースと電気的に接続されている。【選択図】図4