By using chemical combustion theory and variable specific heat capacity approach, a method of calculation and analysis of thermal performance parameters of micro-turbine device on a regenerative cycle is presented. The impact on device performance of pressure ratio of compressor, heating ratio, heat rate of fuel and effectiveness of recuperator is discussed. A case about 60 kW micro-turbine is showed, which provides a useful and feasible way as a reference for reasonably choosing and designing a micro-turbine device. The thermal performances of CHP system consisted of micro-gas-turbine and water heater have also been calculated.