The cooling system of a plastic injection mould is important as it affects the quality and productivity of the polymeric components or assemblies. Contemporary cooling channel design is confined to simple configurations of straight-drilled coolant passageway around the mould insert. Undesirable defects resulted during injection moulding, such as warpage, are inevitable. The application of rapid tool (RT) based on solid freeform fabrication (SFF) technologies with conformal cooling channel (CCC) design has provided a profound opportunity in quality improvement of polymeric components. In this study, a novel design of variable radius conformal cooling channel (VRCCC) is proposed to achieve better uniform cooling performance. Thermal-FEA and melt flow analysis are used to validate the method.