<p>Most of the studies on abrasive waterjet (AWJ) machining in the literature are focusing on planar surface cutting or linear cutting, which is not applicable for high-quality cutting of complex surface workpieces. This is mainly due to the difficulty in accurately controlling the jet impact angle and standoff distance (SOD) during the cutting process. Aiming at solving this problem, a three-step method was proposed for complex surface cutting and kerf taper angle (KTA) was used as an example for the optimization. Four main processing parameters, including waterjet pressure (<i>P</i>), SOD (<i>s</i>), traverse speed (<i>u</i>), and abrasive mass flow rate (<i>m</i>_a), were considered to achieve the minimum KTA. Planar surface cutting tests were first performed to establish a prediction model of KTA, which was then optimized by the mountain gazelle optimizer (MGO) algorithm. Both the prediction model and the optimization results were validated by experiments, and the average errors were 2.60% and 1.09%, respectively. Subsequently, binocular structured light technology was employed to reconstruct the complex surfaces, followed by normal vector estimation, slicing, normal vector offset, and coordinate transforming. Finally, the curved cutting path ensuring a constant SOD and jet impact angle was generated, which could maximumly improve the KTA by 74.725% with a value around 1.7843°. This research introduces a systematic method for high-precision cutting of complex surfaces using AWJ technology.</p>