An objective lens for endoscopes comprises a front lens unit component and a rear lens unit component, between which a stop is located, wherein a front lens unit component comprises, in order from the object side, a first lens having a negative refractive power and a second lens having a positive refractive power which directs a surface of the small radius of curvature toward the object side; wherein a rear lens unit component comprises a third lens having a positive refractive power which directs a surface of the small radius of curvature toward the image side, a fourth lens having a positive refractive power and a fifth lens having a negative refractive power; and wherein the fourth lens and the fifth lens are cemented, and satisfying the following condition:

where f is the composite focal length of the total system and f3 is the focal length of the third lens.

 
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