Surface micro-texturing represents an emerging pivotal technology for enhancing surface properties to satisfy the requirements of diverse applications. However, fabricating complex, multiscale micro-textures on variable-curvature surfaces, such as face gears, remains challenging for conventional methods due to high process interference and limited machining precision. In this study, a hierarchical micro-texturing method employing ultrasonic vibration assisted 5-axis ultra-precision turning (UA5UT) is presented. The method first establishes a kinematic model for UA5UT by synchronizing tool orientation and vibration position in real-time with respect to time t. Subsequently, an equal arc-length tool path planning method is proposed to enable the precise generation of hierarchical micro-textures. Furthermore, the mechanisms underlying the formation of hierarchical micro-textures in the UA5UT process are elucidated, and a predictive model for the resulting micro-texture topography is developed. The simulation result demonstrates that submicron-sized secondary sine-wave micro-texture units are uniformly distributed on micron-sized primary micro-textures, exhibiting significant periodicity and high adaptability to surface curvature variations. Finally, based on the proposed UA5UT process, a hierarchical micro-texture fabrication strategy is proposed for face gear tooth surface, offering a novel approach for the manufacturing of high-performance face gears.