In this study, 3 mol% Y2O3-stabilized zirconia (3Y–ZrO2) and commercially pure titanium (cp-Ti) joints were fabricated with an Ag68.8Cu26.7Ti4.5 interlayer (Ticusil) at 900 °C for various brazing periods. After brazing at 900 °C/0.1 h, Ti2Cu, TiCu, Ti3Cu4, and TiCu4 layers were present at the Ti/Ticusil interface, while TiCu and TiO layers were observed at the Ticusil/3Y–ZrO2 interface. In the residual interlayer, clumpy TiCu4 was formed along with the Ag solid phase. After brazing at 900 °C/1 h, Ti3Cu3O and Ti2O layers were formed at the interlayer/ZrO2 interface, while Cu2O was precipitated in the residual interlayer with $\left[ {111} \right]_{{\rm{Cu}}_{\rm{2}} {\rm{O}}} //\left[ {111} \right]_{{\rm{Ag}}}$ and $\left( {20\bar 2} \right)_{{\rm{Cu}}_{\rm{2}} {\rm{O}}} //\left( {20\bar 2} \right){}_{{\rm{Ag}}}$. After brazing at 900 °C/6 h, a two-phase (α-Ti + Ti2Cu) region was observed on the Ti side with $\left[ {2\bar 1\bar 10} \right]_{{\rm{\alpha - Ti}}} //\left[ {100} \right]_{{\rm{Ti}}_{\rm{2}} {\rm{Cu}}}$ and $\left( {0002} \right)_{{\rm{\alpha - Ti}}} //\left( {0\bar 13} \right)_{{\rm{Ti}}_{\rm{2}} {\rm{Cu}}}$, while the TiCu layer grew at the expense of Ti3Cu4 and TiCu4. The bonding mechanisms and diffusion paths were explored with the aid of Ag–Cu–Ti and Ti–Cu–O ternary phase diagrams.