This endoscope (1) comprises an observation optical system (3) which can switch between magnified observation and normal observation, and a plurality of illumination optical systems (4A, 4C). The leading lens surfaces (4a, 4c) of the illumination optical systems (4A, 4C) are located closer to the base side than the leading lens surface (3a) of the observation optical system (3), and the leading lens surfaces (4a, 4c) of all of the illumination optical systems (4A, 4C) are positioned substantially parallel to the leading lens surface (3a) of the observation optical system (3). The following conditional expressions are satisfied: 1.0≤D_Back(far)/D_Back(near)<3.0 0.015
