Titanium dioxide nanotubes (TiO2-NT) have been synthesized via an electrochemical anodization strategy followed by calcination under different temperatures to form TiO2 nanostructures of anatase and rutile crystal phases. The nanotube-on-Ti structure is further used as a substrate for calcium hydroxyapatite (HAp) coating. The effect of TiO2 morphology and crystal phases (i.e. amorphous, anatase and rutile) on the coating efficiency of HAp has been investigated in comparison with HAp coating on bare Ti metal. The HAp coated TiO2-NT have been studied using X-ray absorption near-edge structure (XANES) at the Ti K- and Ca K-edge. The results show that TiO2 of amorphous and anatase phases are of comparably good performance for HAp crystallization, and both are better than rutile TiO2, while HAp is hardly found on bare Ti. The implications of the findings are discussed.