In general, the operating characteristics of solid-state lasers are significantly impacted by the ambient temperature, especially for Yb:YAG crystal with an anti-Stokes fluorescence cooling effect. In this Letter, the influence of the ambient temperature on the operating characteristics at the zero thermal load (ZTL) state is studied for an Yb:YAG disk crystal with a 1030 nm intra-cavity-pumped scheme. Theoretical analysis indicates that the output power of the laser at the ZTL state is significantly enhanced as the ambient temperature increases. Experimental results show that when the ambient temperature increases to 40°C, the output power of the laser at the ZTL state can reach 1.11 W, which is more than twice than that achieved at an ambient temperature of 25.5°C. This Letter provides a technical pathway for achieving a higher-power radiation-balanced laser (RBL).