An imaging unit, an imaging module, and an endoscope system capable of obtaining a high quality image while reducing the diameter of the distal end of the insertion portion. The image pickup unit 10 according to the present invention includes an image pickup element, a semiconductor package 20 having a connection electrode 21 formed thereon, a circuit board 30 connected to the semiconductor package 20 on the f 3 plane, at least f 5 plane, f 6 plane, and f 7 An odd-shaped circuit board 40 having a connection electrode formed on its surface and connected to the circuit board 30 at f 5 plane, electronic components 51 and 52 mounted on the f 4 surface of the circuit board 30, f 6 face f 7 of faulty circuit board 40, f 7 And a plurality of cables 60 connected to the connection electrodes of the circuit board 30 and the irregular circuit board 40, and the electronic components 51, 52 are housed in the recess 43 formed on the f5 surface of the heterogeneous circuit board 40, , And the plurality of cables 60 are contained within the projection plane in the optical axis direction of the semiconductor package 20.挿入部先端の細径化を図りながら、高画質の画像を得ることのできる撮像ユニット、撮像モジュールおよび内視鏡システムを提供する。本発明における撮像ユニット10は、撮像素子を有し、接続電極21が形成された半導体パッケージ20と、f3面で半導体パッケージ20と接続される回路基板30と、少なくともf5面、f6面、およびf7面に接続電極が形成され、f5面で回路基板30と接続される異形回路基板40と、回路基板30のf4面に実装される電子部品51、52と、異形回路基板40のf6面、f7面の接続電極に接続される複数のケーブル60と、を備え、電子部品51、52は、異形回路基板40のf5面に形成された凹部43内に収容され、回路基板30、異形回路基板40、および複数のケーブル60は、半導体パッケージ20の光軸方向の投影面内に収まることを特徴とする。
