Detailed analysis of the spectroscopic properties of the YAlO(3) crystals doped with manganese ions has been performed. The exchange charge model of the crystal field was used to calculate the crystal field parameters and energy levels of the Mn(4+) and Mn(5+) ions in YAlO(3). It was shown that both ions contribute to the formation of the absorption spectra. The calculated energy levels are in good agreement with the main observed absorption peaks. Comparison of the Racah parameters B for both ions in YAlO(3) with those for free ions shows a significant role played by the covalent effects, especially for Mn(5+).