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We have formed insulated molecular wires of conducting polymers, polyaniline (PANI), and cyclodextrin (CD) or the molecular nanotubes synthesized from CDs, and observed the structures of the wires by atomic force microscopy (AFM). CD or the molecular nanotube can isolate a single conducting polymer chain by shielding the attractive interaction between polymer chains. In addition, since CD or the nanotube confines the conformation of the polymer chain to a rodlike one owing to the very small cavity, the defects of the π-conjugated system should be suppressed on the polymer chain. Further four-term electrodes with gaps of the order of 100 nm have been made by two different methods using AFM, the tip-induced local oxidation and AFM lithography, in order to measure the conductivity of the insulated molecular wires. With the electrodes fabricated by the tip-induced local oxidation, it was difficult to measure the conductivity because of the native oxide layer on the electrode surface. On the other hand, the AFM lithography provided us with the electrodes appropriate for the conductivity measurements of molecular wires.