Thin electroless polytetrafluoroethylene (PTFE) film was deposited to the surface o f metal

which can decrease the surface energy of metals. Dropwise condensation occurred at the surface of these films instead of filmwise condensation. Hence the high heat transfer coefficient can be realized. It is caused by the difference of surface energy between liquid and solid. The solid surface energy was measured from the contact angles. The result of experiment consists with analysis. The effect of PTFE content and surface aging to heat transfer were investigated.