The process cycle time in injection moulding process depends significantly on the cooling time of the plastic part, which is facilitated by the cooling channels in the injection mould. Effective cooling channel design in the mould is important because it not only affects cycle time but also the part quality. Conventional cooling channels are normally made of straight drilled holes in the mould, which have limitations in geometric complexity as well as cooling fluid mobility within the injection n mould. Over the years, conformal cooling techniques are being introduced as effective alternative to conventional cooling. Many process of Rapid Tooling (RT) have been proven useful for designing the conformal cooling channels to enhance the cooling time for injection moulding process. Nevertheless, no studies had been published where the additive fabrication technique of three-dimensional printer (3DP), has been used to make an injection molding tools extended to the optimum configuration of fin trees in cooling channels of injection molding process. At one point, the cooling effectiveness of the fin tree would approach an asymptotic limit. Further attempts at improvement would not give benefits commensurate with the required effort. To identify this optimum solution is the ultimate objective of the chosen research problem by combining both experimental and numerical approaches. Design of mould was carried out using commercial computer aided design software Solid Work while the part cooling time is optimized by conformal cooling channels in the mould using the ANSYS thermal analysis software. © 2011 IEEE.