Infrared spectroscopy is a modern method of analysis suitable for the investigation of urinary stones composition. Urinary stone disease or urolithiasis has afflicted mankind for centuries and continues to be a significant medical ailment throughout the world. Therefore, identification of components of urinary stones is essential to provide information about etiological factors considered responsible for stones formation making the therapy and the prevention possible. This paper presents the results of the IR spectrum study of urinary stone of patient from Moldova, containing as a main component whewellite or calcium oxalate monohydrate СаС2О4  Н2О. IR spectrum was recorded on a FTIR Spectrometer Spectrum 100, PerkinElmer in the range of 4000-650 cm-1 with use of ATR accessory. Analyzed stone previously was homogenized in an agate mortar. The IR spectrum is represented in the figure below. In the region 3500 – 3000 cm-1 we can see five bands of absorbance 3476, 3434, 3329, 3250, 3053 cm-1 belonging to the symmetric s(О-Н) and asymmetric as(О-Н) stretching vibrations of crystallization water. The IR spectrum bands of 1611 cm-1 and 1314 cm-1 correspond to the symmetric s(C-O) and asymmetric as(C-O) stretching vibrations of oxalate groups. As well bands at 1611, 1314, and 779 cm-1 are due to as(C=O), s(C=O), (O-C=O) frequencies of the oxalate part. Weak absorbance at 1092 cm-1 corresponds to as(PO43-) of calcium phosphate. Thus the analyzed stone contains whewellite as the main component and a very small impurity of calcium phosphate.