Zoom lens and imaging apparatus

A zoom lens substantially consisting of a first lens group having a negative refractive power and a second lens group having a positive refractive power, disposed in order from the object side, wherein:

• zooming is performed by moving the first lens group and the second lens group;
• the first lens group is substantially composed of four lenses;
• the object side surface of the second lens from the object side in the first lens group is a surface concave on the object side in the paraxial region;
• the second lens group is substantially composed of a first lens having a positive refractive power, a second lens having a positive refractive power, a third lens having a negative refractive power, and a fourth lens having a positive refractive power, disposed in order from the object side;
• and
• when the focal lengths of the first lens and the second lens from the object side in the second lens group are taken as fG21 and fG22 respectively, the zoom lens satisfies a conditional expression given below:
• 1.3<fG21/fG22<3.0 (3-1).