ZrO2/SiO2 multilayer mirrors at normal incidence are deposited on the infrared quartz substrates for the application of holmium laser. The deposition process is optimized to overcome the water intrinsic absorption, surface scattering loss, mechanical stress of thin film materials. The transmittance and the surface roughness of mirror is less than 0.1% at the wavelength of 2.1 μm and 1nm, respectively. The deposited mirrors show long-term stability and high reliability in the application of holmium-laser system.