An endoscope includes a heat influence reducing portion that radiates heat, which is generated with light guiding of a light guide portion via a position near a second lens and conducted to the second lens, to a frame member to reduce a local temperature difference in the second lens in a projecting portion in which a first lens of a front observation window through which an inserting direction for insertion into a lumen is observed and the second lens having a truncated conical shape used for observing a viewing field region of a side observation window through which a direction crossing the inserting direction is observed are arranged.
