Hydroxyapatite is the main inorganic component of human bones and teeth. It is an excellent bone repair material, which has good biocompatibility and biological activity, and can induce the growth of bone tissue and promote the repair of tissue defect. In recent years, nano-hydroxyapatite has exhibited new application functions in the field of biomedicine due to its unique properties. However, in order to take advantage of the unique functional properties of nano-hydroxyapatite, it is often necessary to modify its surface to meet the conditions and requirements of biomedical applications. From the perspective of biomedical applications, the research on surface modification of hydroxyapatite nanoparticles was reviewed for the applications in biological imaging, DNA transfection, drug delivery, compounding with polymers, promotion of bone formation and bacteriostasis, etc. Besides, the related surface modification ideas, techniques and application effects of modification were also discussed. The surface modification can not only improve the dispersibility and suspension stability as well as the drug loading capacity and promoting bone formation ability of hydroxyapatite nanoparticles, but also provide new functions including biological imaging ability, active targeting function and bacteriostatic ability. In short, the surface modification is an effective way to promote the biomedical application of hydroxyapatite nanoparticles.