NiCrAlY+YSZ thermal barrier coatings (TBCs) were deposited on HA188 alloy using air plasma spraying technique. The cyclic oxidation behavior of TBCs was studied at 1100 oC, 1120 oC and 1150 oC high temperature. The results indicated that TBCs lifetime significantly decreased with the increasing of thermal cyclic temperature. The failure of TBCs was attributed to the formation and propagation of crack in YSZ layer near the YSZ/NiCrAlY interface. XRD analysis indicated that the phase composition of YSZ top coat had no change during all thermal cyclic process, and kept the same metastable tetragonal-prime (t"-ZrO2) structure. It was proposed that thermally grown oxide (TGO) growth following a parabolic law had an important effect on the formation and propagation of crack in YSZ.