In this study, the influence of abrasive water jet machining (AWJM) parameters such as water pressure, standoff distance, and traverse speed each at three different levels were analyzed on the surface roughness of the Al- graphite composites which are fabricated through the squeeze casting method. The experiments were conducted using L9 Taguchi technique. The percentage contribution of each process parameter on surface roughness was analyzed by means of analysis of variance. The contribution of water pressure on surface roughness was found to be more significant than traverse speed and standoff distance. Linear regression model was developed to predict the surface roughness.