In　this　research,　densely　aligned　TiO2　nanorods　are　etched　into　nanotubes　by　hydrochloric　acid,　and　the　growth　mechanism　is　also　supposed.　During　the　etching　process,　the　dents　appear　from　the　top　down　and　inside　out　along　the　growth　direction　of　the　nanorod,　and　finally　form　the　tube　structure.　Actually,　the　nanotube　with　square　hollow　cross　section　consists　of　a　mass　of　surrounded　fine　nanowires,　which　will　be　teared　into　independent　ones　at　high　temperature.　When　assembled　into　dye　sensitized　solar　cells(DSSCs),　the　photoelectrical　conversion　efficiency　of　TiO2　nanotubes　is　much　higher　than　that　of　nanorods,　and　the　highest　value(3.26%)　is　located　at　the　etching　temperature　of　140℃.　It　could　be　deduced　that　the　increased　specific　surface　area　and　length　shortening　of　the　nanotube　play　the　positive　and　negative　effect　on　the　photoelectrical　property,　respectively.　Furthermore,　the　calcination　effect　on　the　structure　and　photovoltaic　property　of　TiO2　nanotubes　is　also　carried　out.　However,　the　fracture　and　aggregation　of　nanotubes　could　be　observed　after　heating　treatment,　which　therefore　increase　the　difficulty　of　photo-induced　carriers　in　directional　transfer　and　also　reduce　the　photoelectrical　activity.　©　2019,　Science　Press.　All　right　reserved.