Congruent Zr/Er:LiNbO3 and Zr/Er/Yb:LiNbO3 crystals were grown by the Czochralski technique. The structural properties of the grown crystals were confirmed by the powder X-ray diffraction (XRD) patterns. The introduction of Zr4+ ions decreased the intensities of the green and red upconversion emissions in Er:LiNbO3 crystal. The green emission resulted from the two- and three-photon processes in Zr/Er:LiNbO3 crystal, and the suppressed cross relaxation processes H-2(9/2)+I-4(15/2)-> H-2(11/2)/S-4(3/2)+I-4(13/2) and I-4(11/2)+I-4(11/2)-> F-4(7/2)+I-4(15/2) were contribution to the reduced green and red emissions. Zr4+ ions doping shortened the lifetime of the S-4(3/2)-> I-4(15/2) transition, which was responsible for the decreased green emission in Er:LiNbO3 crystal. In the case of Zr/Er/Yb:LiNbO3 crystal, an enhancement of red emission with respect to the green emission was observed. It was proposed that there was a possible cross relaxation process I-4(13/2)+I-4(13/2)-> F-4(9/2)+F-4(15/2) in Zr/Er/Yb:LiNbO3 crystal. (C) 2012 Elsevier B.V. All rights reserved.