In this graduated essay is presented a project of power plant steam turbine with nominal power 50 MW. The turbine is assembled as a two-case turbine, high-pressure turbine and low-pressure turbine, while steam re-heater is used for steam re-heating before its entrance into the low-pressure turbine. Steam re-heating is performed with steam delivered directly from steam generator. It is performed thermodynamic calculation and analysis of steam turbine according to given steam operating parameters. Based on a given data a thermodynamic calculation of high-pressure, low-pressure and the whole turbine in two operation modes (with re-heating and without re-heating) were made. Thermodynamic calculation resulted with a following data: real and ideal power, energy efficiency, energy losses, energy flow, steam mass flow rate, specific enthalpy and steam content in low-pressure turbine. Energy and exergy analyses of high-pressure, low-pressure and the whole turbine were made after performed thermodynamic calculation. Presented analysis resulted with following main conclusion: steam re-heating in proposed combination has a positive influence only on the content of steam which expanded in low-pressure turbine. Increase in steam content during the re-heating usage, significantly increases operating period of low-pressure turbine (maintenance reduction). All the other operating parameters of the whole analyzed turbine during steam re-heating are worse in comparison with process without the re-heating usage (developed power and efficiencies decreases, while losses simultaneously increase).