This paper presents a new type of three‐dimensional variable‐angle electro‐osmotic micromixer. By introducing the electric field effect into it, the voltage, baffle structure, and electrode structure in the mixing process are studied. The results show that when the voltage value is close to 1 V and the baffles are alternately placed at an angle of 30°, the micromixer performs best. At low Reynolds numbers (Re), the electric field is closely related to the mixing efficiency, which proves that the alternating placement of microelectrodes can effectively improve the mixing efficiency. This study provides a new method for improving the mixing efficiency of micromixers and has broad application prospects in many fields such as chemical analysis, drug delivery, and biological detection.