The efficiency of micro gas turbine generator is affected significantly by the temperature level in the micro gas turbine system. If the operation temperature of generator and compressor increases, the efficiency of generator and compressor decreases, greatly. This study investigates the heat transfer and temperature distribution in a micro gas turbine system. In addition, the temperature levels on the substrates are controlled using the different thermal insulation materials. The thermal conductivity of insulation is changed from 0.1 to 100 to evaluate the effect of the thermal conductivity on generator and micro gas turbine. A conjugate heat transfer method has been used for this purpose. We conducted a CFD analysis in the compressor and turbine flow domains using CFX v.12 to obtain the boundary conditions for conduction calculation. The conduction analysis, using ANSYS v.12, was calculated on the solid part domain. The conduction heat transfer calculation considered the heat generation induced by the joule heating in the generator. The results show that the most heat flux from the turbine and generator is removed by the inlet flow induced by the compressor. The conductivity of thermal insulation material has a little effect on the temperature distributions of the generator. (C) 2013 Elsevier Ltd. All rights reserved.