This study is mainly to control the density of zinc oxide nanowires arrays as main axis. We spin coated AZO thin film to Si/SiO2 substrate by hydrothermal method growing ZnO nanowire arrays on a substrate by spin coating a layer of zinc powder mixed with SiO2 film, and controlled the concentration of zinc. We can easily obtain a nanowire array density control. In this experiment, we investigated different centrifugation speed, time, zinc concentration, temperature and other variable parameters. Through field emission scanning electron microscopy observation of dispersive zinc oxide nanowires and dispersion situation, it was found that using different doping concentration and rotation speed, different densities can be successfully obtained for ZnO nanowires array. Dispersion of zinc oxide nanowires by hydrothermal method with increasing time, the diameter and length will increase significantly.