BACKGROUND: Fundamental investigation of the issue how various factors influence on origin and behavior of the nephrolithiasis is very actual because of necessity of the information about of early diagnostic methods as well as a prognostication. So, the information about of formation dynamics of phase and elemental composition of oxalate-calcic nephrolithes pending of lifetime of one patient is useful. AIM: The aim of the investigation is to obtain the information about of elemental composition as well as phase composition of the one patient nephrolithes formed pending of lifetime. MATERIALS AND METHODS: In the paper the data of the careful investigation of the elemental and phase composition of the two nephrolithes ablated from one patient at different times are presented. First nephrolith had been ablated from the right kidney in the March of 2002 (patient was 41 years old), subsequently second that had been did from the left kidney in the December of 2019 (patient was 58 years old; the nephrolith was found in 2012). The study was carried out using mass spectrometry and atomic adsorption spectrometry with inductively coupled plasma, infrared spectroscopy, X-ray phase analysis, CHN/S analysis. RESULTS: Both calculi were calcium oxalate, predominantly Vevellite structures. The chemical composition of the both nephrolithes is alike. They contain microimpurities of all essential as well as conditionally essential elements. Quantities of the toxic elements in the nephrolithes are identical too. Microquantities of the nitrogen and sulphur indicate a presence of amino acids and proteins in the nephrolithes structure. CONCLUSIONS: The results indicate that the nephrolithes with invariable phase and elemental composition would be forming in the different kidneys of one patient pending of lifetime.