The dimensional accuracy and surface finish of ice patterns generated by rapid freeze prototyping were first investigated. The dimensional accuracy and surface finish of metal parts made by investment casting with ice patterns were then investigated and compared with those made by conventional investment casting with wax patterns. The selection of binder, ceramic powder, and catalyst material for ceramic slurries in the process of investment casting with ice patterns and the need for an interface agent to separate the ice pattern from the ceramic slurry in the mold making process are discussed. The parts used in the investigation included circular cylinders with vertical and slant walls and a turbine impeller.