Abstract: To investigate the influence of ultraviolet nanosecond laser processing on the microtexture dimensions of diamond-coated surfaces and to select the laser processing parameters that could produce high-quality microtextures, in this study, based on the single-factor experiments, the microtexture experiments were performed on diamond-coated surfaces with varying processing power, processing speed and number of passes by using the nanosecond laser equipment. The experimental results indicate that ultraviolet nanosecond laser processing power, speed, and number of passes significantly affect the texture dimensions and quality. The width, depth and heat-affected zone (HAZ) of the textures increase with higher laser processing power but decrease with the increased processing speed. Within a certain range of passes, the width and depth of the textures increase with the number of passes; however, beyond this range, the rate of increase in texture depth and width slows down. Based on the single-factor experiment results, it is found that selecting a processing power of 8.3 W, a processing speed of 80 mm/s, and five passes yields larger texture dimensions, better quality, and a smaller HAZ on the diamond-coated surfaces. This study provides theoretical guidance for parameter selection in nanosecond laser processing of textures on diamond-coated surfaces.