PROBLEM TO BE SOLVED: To provide: a device and a method for holding a substrate which show excellent maintenance capability an imaging device and an endoscope.SOLUTION: A dented mold 3 and a protruded mold 4 are constituted of a fluorine resin. An imaging module 16 comprises a flexible substrate 7, a CCD 11, and electric circuit components 13a-13d mounted on a surface of the flexible substrate 7. A thermosetting resin 18 is applied to the flexible substrate 7. After the imaging module 16 having the flexible substrate 7 folded into a laterally-facing U-shape is inserted into an insertion dented part 3a of the dented mold 3, a protruded part 4a of the protruded mold 4 is inserted into the insertion dented part 3a. The flexible substrate 7 is sandwiched between the protruded mold and the dented mold 3 by pushing a folded part 7b of the flexible substrate 7 by the protruded part 4a and pressing the flexible substrate 7 against a bottom part of the insertion dented part 3a to make the flexible substrate into substantially a U shape. When the thermosetting resin 18 is cured by heating, the electric circuit components 13a-13d, a connecting terminal 14, and a signal cable 15 are sealed. Further, the flexible substrate 7 is fixed in a shape where the flexible substrate is folded into substantially the U shape.
