Abrasive water jet (AWJ), which is a non-traditional machining method, is more widely used today. Various materials such as metals, ceramics, polymers, and composites can be easily machined with AWJ. In this study, cutting of St37 steel plates in stacked form with AWJ was investigated. The experiments were carried out according to the general full factorial design. Experimental parameters were inter-stack distance, traverse speed, and abrasive mass flow rate also each of these parameters was chosen at three levels. Surface roughness and kerf widths were examined to determine the cutting performance. Analysis of variance (ANOVA) of all outputs was provided and thus the effects of experimental parameters and their levels on cutting performance were found. The most effective parameters for surface roughness and kerf width in almost all conditions were abrasive mass flow rate and inter-stack distance, respectively. In addition, a concept for multi-simultaneous cutting was developed with mathematical differences of surface roughness and kerf taper angle. Thus, optimum levels of experimental parameters were found for minimum mathematical differences.