Objective By comparison with atmospheric plasma spraying and high velocity oxygen fuel spraying, the microstructure characteristics of the HA coating deposited by micro-plasma spraying were investigated. Methods High crystallinity hydroxyapatite powders were used as initial material, which were deposited onto Ti-6Al-4V substrate by three different spraying technologies: micro-plasma spraying (MPS), atmospheric plasma spraying (APS) and high velocity oxygen fuel (HVOF) spraying in this research. The morphology, phase composition and preferred crystal orientation of HA coatings were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). Results Compared with the other two counterparts, micro-plasma sprayed HA coating exhibited flat and dense surface without obvious porosity and void, the cross section of which exhibited a typical lamellar structure, with the emergence of columnar crystal near coating surface. Besides, the coating had high crystallinity (>90%) with only a small amount of amorphous phase and decomposition phase, which was assumed to be related to the stability of the coating in the body fluid environment. Conclusion Compared with APS and HVOF, HA coating deposited by MPS exhibited denser structure, higher crystallinity with less decomposition phase, and columnar microstructure was observed within coating.