Aluminium matrix composites find wide applications in the present industrial scenario due to their desirable properties. Study of the effect of process parameters on machinability of aluminium matrix composites is of paramount importance in the field of manufacturing engineering. Machining of a composite depends on the properties and relative content of the reinforcement and the matrix materials as well as on its response to the machining process. In this article, investigations on the machinability aspects of aluminium-silicon carbide and aluminium-graphite composites are presented. Experiments have been carried out through the Design of Experiments technique and regression machinability models have been developed, which express the degree to which the resultant force depends upon the cutting parameters and the percentage of reinforcement present in the aluminium matrix composites machined. A comparative study of the effect of cutting parameters on the resultant force has been presented.