The optical absorption spectrums, level structures and upconversion luminescence of Pr3+ sensitized by Yb3+ in fluorozirconate glass are studied. The results show that Yb3+ ions transfer energy to Pr3+ ions by the energy resonance translation between rare earth ions; the intensity of the upconversion luminescence is the highest when the glass is excited by 880 nm-wavelength light; the intensity is high both when the concentration of Yb3+ is low while the concentration of Pr3+ is high and when the concentration of Yb3+ is high while the concentration of Pr3+ is low.