Nanochannel　system　provides　a　promising　platform　to　create　nanofluidic　components　in　large-scale　integrated　circuits　for　＂lab-on-a-chip＂　applications.　However,　it　is　a　big　challenge　to　achieve　in　situ　monitoring　on　microscopic　nanofluidic　manipulation　of　single　nanofluidic　components　in　the　integrated　ionic　circuit.　Herein,　we　present　a　simple　approach　to　realize　visual　nanofluidic　manipulation　in　asymmetric　nanochannels　by　the　functionalization　of　an　electrochromic　polyaniline　coating,　which　demonstrates　redox-tunable　surface　charge　accompanied　by　a　visible　color　variation.　The　electrochromic　nanochannels　present　a　green　color　when　behaving　as　ionic　diodes,　while　the　color　turns　to　light　yellow　in　a　manner　of　ionic　resistor.　Moreover,　both　ionic　transport　behavior　and　color　transition　could　respond　well　with　alternating　switch　between　redox　states,　contributing　to　a　reversible　and　stable　visual　nanofluidic　manipulation　of　electrochromic　nanochannels.　This　work　will　create　new　avenues　on　in　situ　characterizing　nanofluidic　manipulation　of　nanofluidic　components　in　integrated　ionic　circuits　for　intelligent　sensing　and　detection　applications.