Fourier transform infrared (FTIR) spectroscopy is an important tool in the analysis of calcium phosphate. The most commonly used methods are Attenuated total reflectance spectroscopy (ATR) and Transmission FTIR spectroscopy with KBr pellet (FTIR KBr) less frequent - Diffuse reflectance FTIR spectroscopy (DRIFT) and Photoacoustic spectroscopy (PAS). FTIR methods are used for both qualitative analysis and quantitative analysis, for example, the crystallinity index (CI) and estimation of the relative CO32-, OH- and HPO4- content. The main task of this study was to identify advantages and disadvantages of each method in the research of carbonate containing calcium phosphate (CP) powders with different degree of crystallinity. Using statistical methods, we found that the parameters of all four methods are most consistent when we analyzed amorphous or microcrystalline samples. The biggest differences showed crystalline powder. This led to the conclusion that the analysis of such samples is essential both in the choice of methods and in information on the degree of crystallinity. By analyzing both the entire IR spectrum and specific parts of spectra, the greatest differences showed ATR method. This is explained by the low sensitivity of this method in CO32- OH- and H2O.