An imaging apparatus is provided and includes: a solid-state imaging device that receives image light of an observed portion inside of a coelom to output an imaging signal of the image light a cover glass disposed above an light receiving surface of the solid-state imaging device so that the cover glass and the solid-state imaging device are separated with a space and a first circuit board disposed at a vicinity of an upper surface of the cover glass and including a peripheral circuit of the solid-state imaging device, the first circuit board having a thermal conductivity lower than that of a reference circuit board whose major component is alumina, the imaging apparatus being included in a front end of an electronic endoscope.