An experimental and theoretical research work on abrasive waterjet (AWJ) oscillation cutting of Glass Fiber Reinforced Polymer (GFRP) composite materials was conducted at the Water-jet Laboratory of the Industrial Research Institute of Swinburne (IRIS). The objective of this research work was to conduct a comparative study of the oscillation and normal (without head oscillation) cutting of GFRP composite materials and compare the performances the two processes. This new technique which is a variant of the traditional AWJ cutting technique, makes use of a back and forth motion of the cutting head which is superimposed on the normal linear motion to effect optimum loading of the cutting forces on the workpiece material and scan the cut-wall surface to also improve surface finish. The technique was used for cutting GFRP composites materials and the qualities of resulting surfaces were measured using stylus type equipment. A comparison of the results indicates that there is significant improvement in the quality of surfaces produced by head oscillation technique than normal AWJ cutting. In some of the samples, an improvement, in surface quality, as measured by Ra values, up to 20 percent was found.