This work was carried out in order to study the heat transfer and air flow by natural convection in a domestic refrigerator (without ventilation). Three configurations were investigated: empty refrigerator with and without shelves and loaded refrigerator. Both experimental and numerical approaches were used. Simulations using a CFD software was undertaken supposing a constant evaporator temperature and laminar 3D-flow. Air temperature and velocity fields were shown. It was found, for all cases studied, that the warm zone is located at the top of the refrigerator and the cold zone at the bottom. The air temperature obtained from simulations was compared with the experimental values. Good agreement was obtained particularly at the bottom part of the refrigerator. However, in the cases of empty refrigerator (with and without shelves), the model over predicted the air temperature at the top part. This may relate to the fact that radiation was not taken into account in the model.