Due to the different vapor pressures between SrO and ZrO₂, composition of air plasma sprayed (APS) SrZrO₃ coating deviates from stoichiometric SrZrO₃, resulting in formation of second phase ZrO₂ in the as-sprayed SrZrO₃ coating. To obtain single-phase coating with high phase stability, the Sr_1.1(Zr_0.9Yb_0.05Gd_0.05)O_3.05 powder with excess Sr was synthesized by solid state reaction and spray drying, followed by air plasma spray to obtain the Sr_1.1(Zr_0.9Yb_0.05Gd_0.05)O_3.05 coating. Thermo-physical properties and thermal cycling behavior of the Sr_1.1(Zr_0.9Yb_0.05Gd_0.05)O_3.05 coating were investigated. Experimental results showed that the Sr_1.1(Zr_0.9Yb_0.05Gd_0.05)O_3.05 coating had no second phase and showed a good high-temperature phase stability after heat- treatment at 1600 ℃ for 360 h. The sintering rate of the as-sprayed Sr_1.1(Zr_0.9Yb_0.05Gd_0.05)O_3.05 coating was 7.27×10 ^-6 s ^-1. Thermal expansion coefficients (TECs) and thermal conductivity of the coating after heat-treatment at 1600 ℃ for 360 h were (9.0-11.0)×10 ^-6 K ^-1 (200-1400 ℃) and 2.83 W/(m∙K) (1000 ℃), respectively. Thermal cycling lifetime of the Sr_1.1(Zr_0.9Yb_0.05Gd_0.05)O_3.05/YSZ double ceramic layer coating was 1000 cycles, due to failure occurring in the Sr_1.1(Zr_0.9Yb_0.05Gd_0.05)O_3.05 coating. Moreover, singe-phase Sr_1.1(Zr_0.9Yb_0.05Gd_0.05)O_3.05 coating with SrZrO₃ structure could be prepared by adding excess SrO in the feedstock, which showed higher TEC by co-dopping with Yb₂O₃ and Gd₂O₃ and sintering resistance than did the SrZrO₃ coating. However, the thermal conductivity of the Sr_1.1(Zr_0.9Yb_0.05Gd_0.05)O_3.05 coating is higher than that of the SrZrO₃ coating because of the absence of the second phase.