In the present paper, numerical analysis of the thermodynamic cycle with the high-temperature nuclear gas reactor (HTGR) for electricity and hydrogen production have been done. The analysed system consists of two independent loops. The first loop is for HTGR and consists of a nuclear reactor, heat exchangers, and blower. The second loop (Rankine cycle) consist of up-to four steam turbines, that operate in heat recovery system. The analysis of the system shows that it is possible to achieve significantly higher efficiency than could be offered by traditional nuclear reactor technology (PWR and BWR). It is shown that the thermal efficiency about 52.5% it is possible to achieve when reactor works at standard conditions and steam is superheated up to 530oC. For the cases when the steam has supercritical conditions the value of thermal efficiency is still very high and equal about 50%.