In this paper, a simple two-dimensional theoretical model based on enthalpy formulation of a latent heat storage system has been developed to study the effects of thermo physical properties of heat exchanger container materials on the thermal performance of the storage system. Numerical results show that thermal conductivity, specific heat and density of the heat exchanger container materials increases, the melting time of the PCM decreases. Numerical results also show that high value of thermal conductivity of the heat exchanger container materials did not make significant contribution on the melt fraction. It is also found that initial temperature of the PCM does not have very important effects on the melting time, while the boundary wall temperature play an important role during melting. Copyright (c) 2005 John Wiley & Sons, Ltd.