The wettability and the interfacial interaction between pure liquid titanium and ZrO2 (CaO stabilized) were studied by the self-designed measuring apparatus in argon atmosphere. The morphology and element distribution of the liquid/solid cross section perpendicular to the interface were analyzed by SEM and EPMA. Results show that some chemical reaction occurs in the interface between pure liquid titanium and ZrO2 (CaO stabilized), but it is not severe. The molten titanium is not wet on the ZrO2 (CaO stabilized), with the contact angle of 103°. The total free energy variation of the Ti/zirconia system caused by the liquid/solid interface reaction can explain the influence of interfacial reaction on the wettability.