Mo-Zr alloys were fabricated via a powder metallurgy method. The effects of Zr on sintering densification behavior, microstructure and property of Mo-Zr alloy were studied. The results indicate that the alloy with Zr addition approach full density after sintering, and the solid phase sintering between Mo particles is the main cause for the densification of the alloy. The tensile strength at room temperature of the alloy is effectively enhanced after adding Zr, and continues to rise with the increasing of Zr content. Enhancing the pressing pressure leads to a better density but not to the tensile strength, while increasing sintering temperature will do harm to the property of the alloy. The microstructure analysis reveals that a little part of Zr solves into Mo matrix, which enhances the tensile strength of the alloys signally, while other part of Zr form oxide second phase particles dispersing throughout grain boundary and inner grain and making the grains to be significantly refined