This article is a compilation of ternary alloy phase diagrams for which molybdenum (Mo) is the first-named element in the ternary system. The diagrams are presented with element compositions in weight percent. The article includes 8 phase diagrams: Mo-Nb-Ti isothermal section at 600 °C; Mo-Nb-Ti isothermal section at 1100 °C; Mo-Ni-Ti isothermal section at 1200 °C; Mo-Ni-Ti isothermal section at 900 °C; Mo-Ni-W isothermal section at 700 °C; Mo-Ni-W isothermal section at 1000 °C; Mo-Ti-W isothermal section at 2227 °C; and Mo-Ti-W isothermal section at 1000 °C.