The direct growth and electrochemical (EC) properties of multiwalled carbon nanotubes (MWNTs) on Ti foil have been investigated. The EC properties of MWNTs were probed before and after HNO3 treatment. Cyclic voltammograms (CVs) of HNO3- treated MWNTs showed reversible electron transfer properties. In contrast, the CVs of untreated MWNTs became unstable when the scan rate exceeded 80 mV/ s. The transmission electron microscopy image shows the tip of the MWNT is opened after HNO3 treatment. The stabilization of CVs for treated MWNTs could be due to the faster charge transfer through the graphite edge planes of open tips.