XRD, laser Raman, and UV-visible DR spectroscopies are used to study tetragonal zirconia-supported MoO3 and NiO-MoO3 oxide systems. For the MoO3/t-ZrO2 system, the results indicate that the distorted surface monomolybdate and polymolybdate species are the main species formed in the low and high MoO3 loading samples, respectively. Crystalline MoO3 is formed above its dispersion capacity, and at temperatures greater than or equal to 823 K the supported MoO3 species are partially converted into ZrMo2O8 phase by interaction with tetragonal zirconia (t-ZrO2). Noteworthily, for the t-ZrO2-supported binary oxides system, i.e., the NiO-MoO3/t-ZrO2 system, the species formed on the surface of the t-ZrO2 depend on the loading sequence of the metal oxides. Depositing NiO before MoO3 leads to the formation of a NiMoO4 phase, whereas there is no evidence to show the presence of this phase when MoO3 was added first. The results suggest that molybdenum oxide can substitute and react with the nickel oxide species predispersed on the surface of the zirconia with the formation of a new phase. In contrast, nickel oxide can only disperse by the incorporation of Ni2+ ions into the unoccupied vacant sites on the surface of the support preloaded with molybdenum oxide and interact with the polymolybdate species resulting in the formation of a surface interaction species. The experimentally measured dispersion capacities of MoO3 and NiO on various supports, i.e., on t-ZrO2, and MoO3 or NiO-modified supports, are consistent with the values expected according to the incorporation model. The results emphasize the importance of the surface structure of the support and the calcination temperature on the dispersion of oxide and the formation of different surface species.