The authors describe conductive tip atomic force microscope used for imaging carbon nanotubes at low temperatures. The instrument allows them to measure the tip-nanotube conductance while performing the topographic scan of the nanotubes on a nonconductive Si O2 substrate. For nanotubes weakly coupled to the contacting electrode, they observe the Coulomb blockade pattern in the tip-nanotube conductance. They reversibly modified the conductance pattern by applying the tip pressure. © 2007 American Institute of Physics.