The variations of glass refletance or front reflectance Rf, vacuum reflectance Rv and tran-smittance T of well activated cesium oxide thin films with Ag addition were measured within the visible and infrared range. Rv increases as the amount of Ag increases, but Rf decreases at first, then increases. Optical absorptions of the thin film and silver particles increase as the amount of Ag increases, and its photoemission increases at first, and then decreases. A model with inhomogeneous distribution of silver particles is proposed.