The aim of this study was to compare the plasma protein adsorptive property of the natural hydroxyapatite (HA) and the synthesized HA to human albumin (Alb), fibrinogen (Fib) and immunoglobulin G (IgG). Different methods such as reflectometry interference spectroscopy (RIfS) measuring, Fourier transform infrared spectroscopy (FTIR) analysis and weighing assessment were used to measure the adsorbed amount of Alb, Fib and IgG on the natural HA and the synthesized HA. To compare the adsorptive property of protein adsorbed on these two kinds of materials, the ratio of Alb/Fib (RA/F) and the ratio of Alb/IgG (RA/I) were calculated. The results from all three methods showed that the values of RA/F and RA/I obtained with natural HA were smaller than those obtained with synthesized HA, that indicated that the natural HA adsorbed more human fibrinogen than human albumin and thas it would enhance blood coagulation and in favor of bone repairing.