In this paper, a guarded hot plate (GHP) apparatus utilizing a Peltier module is proposed and developed to precisely measure the thermal conductivity of insulation material. The Peltier module is used to detect a temperature difference with high sensitivity and to precisely measure heat flux. To develop the GHP apparatus, a two-dimensional axisymmetric heat conduction analysis and calibration experiments of thermistors and Peltier module were conducted. In addition, to assess the reliability of the developed apparatus, thermal conductivity measurements for a high-density glass wool and vacuum insulation panel (VIP) were conducted. Based on the results, the expanded uncertainties of the measurements were estimated. Therefore, the apparatus was found to be reliable for conducting precise thermal conductivity measurements not only for conventional insulation materials but also for a VIP. (C) 2015 Elsevier Ltd. All rights reserved.