In the work, poly (vinyl alcohol) doped with potassium chromate with concentration (1, 3, 5, and 7) %. These samples are prepared by casting method and irradiation by fast neutron with flux (10⁵ n.cm^-2.s^-1) at room temperature, and then optical properties of (PVA/K₂CrO₄) are investigated by UV-visible spectroscopy in the wave length (350-1100) nm. These result show that the optical properties change with increase the concentration of K₂CrO₄, and after irradiation especially energy gap.