Hydroxyapatite (HA) coated onto titanium alloys by atmospheric plasma-arc spraying is a promising technique for improving biocompatibility of materials. The tissue adherence to the HA coating increases when compared to the provided by the natural environment of the human body. Hidroxyapatite coating applied to a Ti-6Al-7Nb alloy substrate by plasma spray was characterized morphologically via Scanning Electron Microscopy (SEM) and X-Ray diffraction. X-Ray diffraction results of the HA layer indicated the presence of crystalline HA, amorphous phase and another constituents, like tricalcium phosphate (TCP) and calcium oxide. However, after annealing at a temperature of 600oC there was recristalisation of the amorphous phase and transformation of some of the TCP to HA. SEM results revealed a lamellar morphology which is typical of plasma sprayed surfaces. The HA/alloy interface exhibited some irregularities, however these are not present in the majority of the interfacial area.