The reducibility of synthesized ceria-stabilized zirconia (CSZ) with strong shock-heated test gases is investigated. Free piston-driven shock tube operating at hypersonic speed at Mach number of 6-8 has been used to heat the ultrahigh pure test gases like Ar to similar to 12800 K, N-2 to similar to 7960 K, and O-2 to similar to 5500 K at a medium reflected shock pressure (5.0-7.4 MPa) for a short duration of 1-2 ms test time. Under this extreme thermodynamic condition, test gases undergo real gas effects. The structural and spectroscopic investigations of CSZ (Ce2Zr2O8) after interaction with shock-heated argon gas show pyrochlore structure of Ce2Zr2O7-delta which is observed to be black in color. In presence of shock-heated N-2 gas, CSZ remains in fluorite structure by changing its color to pale green as nitrogen atoms fill oxygen vacancies. After O-2 interaction with the shock wave, CSZ remains pale yellow but the X-ray diffraction pattern shows the presence of monoclinic ZrO2 due to phase separation. During reduction process, Ce4+ has been reduced to Ce3+ which is an unusual effect. In this study, the catalytic and surface recombination effects of CSZ due to shock-induced compression in millisecond timescale are presented.