Microstructures are applied in various fields to improve the friction and lubrication of mechanical components. Through-mask electrochemical etching (TMEE) has shown good feasibility in machining microstructures array. However, the machining precision of microstructures gradually decreases with increasing etching depth in TMEE. Localization and uniformity are essential indicators of machining precision in TMEE. Herein, particle assisted through-mask electrochemical etching (PA-TMEE) method was proposed to improve the localization and uniformity. Firstly, a coupled multi-physical field model, including gas-liquid two-phase flow, particle motion, and electrochemical processes, was established and adopted to predict the profiles of micro pits. Secondly, a comparison experiment between PA-TMEE and traditional TMEE was performed. The experimental results show that using PA-TMEE instead of TMEE resulted in improved localization and uniformity of the micro pits array. Then, the paper analyzed the effect of particle diameter and content on micro pits. When the particle diameter was 40 µm, and the particle content was 6 g/L, the maximum etching factor was 2.4. The minimum coefficient of variation of the diameter and depth of micro pits were 3.3% and 5.2%. Finally, The machining mechanism of PA-TMEE was analyzed by Scanning Electron Microscopy and Energy Dispersive Spectrometer.