Zoom lens and imaging apparatus

A zoom lens comprising, in order from an object side:

• a first lens group having a negative refractive power;
• a second lens group having a negative refractive power;
• a third lens group having a positive refractive power;
• a stop;
• and
• a fourth lens group having a positive refractive power;
• when power varies from a wide angle end to a telephoto end, the first lens group and the second lens group are moved to an image surface along an optical axis and then moved to the object side,
• the third lens group and the fourth lens group are moved to only the object side along the optical axis,
• the first lens group includes at least one aspheric lens, and
• the aspheric lens has an aspheric shape in which a positive refractive power is increased toward the periphery of the lens when a paraxial refractive power is positive and a negative refractive power is decreased toward the periphery of the lens when the paraxial refractive power is negative.