Manufacturing errors are suppressed, and the precision of positioning between an image-acquisition device and an objective lens is improved. An endoscopic image-acquisition unit includes an objective-lens-unit frame that holds an objective lens； and an image-acquisition-device holding frame that is fitted with the objective-lens-unit frame and that holds an image-acquisition device, wherein the objective-lens-unit frame and the image-acquisition-device holding frame are bonded and fixed with a thermosetting resin that is applied to a fitting region of these frames, and wherein, of the outer surface of the frame that is located on the outer side when the objective-lens-unit frame and the image-acquisition-device holding frame are fitted together, the outer surface of the fitting region and the outer surface of the region other than the fitting region satisfy the following conditional expression:α/β>；2 (1)where α signifies the infrared absorption rate per unit area of the outer surface of the fitting region, and β signifies the infrared absorption rate per unit area of the outer surface of the region other than the fitting region.
