Zoom lens system and image pickup apparatus

A zoom lens system and an image pickup apparatus including the same are provided. The zoom lens system includes a first lens group having a positive refractive power, a second lens group having a negative refractive power, a third lens group having a positive refractive power, a fourth lens group having a positive refractive power, and a fifth lens group having a positive refractive power, which are arranged in an order from an object side. When zooming is performed from a wide angle position to a telephoto position, the first lens group, the third lens group and the fifth lens group remain fixed and the second lens group and the fourth lens group move.