Zirconia coating has a lot of promise when it comes to enhancing the optical performance and laser-induced damage threshold (LIDT) of the mirror in laser systems. In this work, a high LIDT ZrO2 coating was created using the sol-gel spin coating technique. The anhydrous ethanol solvent was substituted with alcohol ether solvent, and the spin coating technique was employed to achieve a macro homogeneous and flawless ZrO2 coating. Additionally, organic polymer polyethylene glycol (average Mn 200, PEG200) doping was used to achieve the uniform ZrO2 coating with LIDT. ZrO2-PEG composite coatings with consistent LIDT and exceptional optical properties were created. Alcohol ether solvents helped the sol produce a more homogeneous gel coating on the substrate, as demonstrated by the ZrO2 coating microscope pictures. The LIDT with a 0.5 wt.% PEG200 content was the most uniform. PEG200 organic molecules were able to alter the link state of the ZrO2 particles. The macroscopic mechanical characteristics of the coatings revealed that the hardness and elastic modulus of the ZrO2-PEG composite coating were mostly influenced by the PEG200 content. When the PEG200 content was 0.3 wt.%, the hardness and elastic modulus of the ZrO2-PEG composite coating were the lowest with the highest of the LIDT at 39.25±3.13 J/cm2 (@ 1064 nm, 11 ns, 1 mm2).