The inventive objective lens for endoscopes has independently a zooming function and a focusing function, and is capable of magnified viewing. The objective lens has an angle of view (2ω) of 100° or greater, and comprises a positive first group G1, a negative second group G2 and a positive third group G3. The third group G3 comprises a positive first (3-1) subgroup G31 and a positive second (3-2) subgroup G32. A subgroup in at least the second group G2 moves to (1) bring about a change in the focal length of the whole system and (2) correct an image position for movement in association with a focal length change, and one subgroup in the second group G2 and the third group G3 moves to the image side from a longer side toward a shorter side of the working distance (WD) to (3) correct the focal position for movement in association with a working distance change.