An imaging lens is constituted by, in order from the object side to the image side: a first lens group having a negative refractive power; a second lens group having a positive refractive power; a stop; and a third lens group having a positive refractive power or a negative refractive power. The first lens group has at least two positive lenses, a first positive lens from among the at least two positive lenses being positioned most toward the object side, and three negative lenses being consecutively provided adjacent to the first positive lens at the image side thereof. The first lens group is fixed with respect to an imaging surface, and focusing operations are performed by moving the second lens group and the third lens group.