Abstract: The aim of this manuscript is to improve the interface compatibility between hydroxyapatite and polyacrylonitrile in the composite. Surface modification of hydroxyapatite using acrylic acid is performed. The composite film is prepared via phografting modified hydroxyapatite containing unsaturated double bond onto polyacrylonitrile. The modified hydroxyapatite and modified hydroxyapatite/polyacrylonitrile comoposite films are characterized using Fourier transform infrared spectroscopy, scanning electron microscopy and differential thermal analysis. The appearance of -C=O vibration peak at 1631cm-1 indicates the modification of hydroxyapatite via esterification of hydroxyapatite and acrylic acid. Well-dispersed nanoscale modified hydroxyapatite particles are embedded in polyacrylonitrile substrate. The tensile strength of polyacrylonitrile/modified hydroxyapatite photografting composite film is larger than blended one. The adsorption amount of photografting composite film is slightly less than blended one.