An objective lens for endoscopes is constituted essentially by, in order from the object side: a negative first lens having a concave surface toward the image side; a first cemented lens, formed by cementing a second lens and a third lens having refractive powers with signs opposite each other, provided in this order from the object side, together; a stop; a positive fourth lens having a convex surface toward the image side; and a second cemented lens, formed by cementing a positive fifth lens and a negative sixth lens, provided in this order from the object side, together, in which the coupling surface is convex toward the image side. Focusing from an object at a most distant point to an object at a most proximal point is performed by moving only the second cemented lens. A predetermined conditional formula is satisfied.