In　this　work,　high-quality　free-standing　ZnO　single-crystal　microtubes　with　hexagonal　cross-section　were　fabricated　by　an　optical　image　furnace.　Optical　vapor　supersaturated　precipitation　(OVSP)　and　axial　photothermal-decomposition　were　proposed　to　interpret　the　microrods　growth　and　microtubes　formation,　respectively.　The　maximum　dimensions　of　the　grown　microtube　were　5　mm　in　length,　100　mu　m　in　diameter　and　1　mu　m　in　facet　wall　thickness.　In　our　previous　work,　a　new　room-temperature　photoluminescence　(PL)　peak　(similar　to　392　nm)　of　ZnO　microtubes　was　attributed　to　VZn-related　donor-acceptor-pairs　(DAP)　transition.　This　work　further　confirmed　the　VZn-related　acceptors　widely　existing　during　ZnO　microrods/　microtubes　growth　by　OVSP.　The　effects　of　major　growth　parameters　(e.g.　lamp　power,　filament　geometry　and　growth　platform　shape)　on　temperature　field　at　the　growth　platform　of　precursor　rod　were　studied　by　a　finite　element　model　as　well.　The　lamp　power　of　65%　(1500　W),　thick　single-filament　and　appropriate　conical　growth　platform　were　optimized　for　a　uniform　temperature　field　to　achieve　consistent　finish　quality　of　microtubes　and　prevent　twin-microtubes　formation.　This　work　would　be　beneficial　for　batch　growth　of　the　novel　ZnO　microtubes/microrods　with　high　quality　for　a　variety　of　applications.