An experimental study for the flow in an axisymmetric cavity of rectangular tube was performed. The pressure and heat transfer coefficient along the side and opposite-walls of the cavity were measured. The cavity length was varied from 80mm to infinity during the experiment. As the result of this study, it was found that as the length of cavity increased beyond the reattachment point, the heat transfer coefficient decreased. It was also found that the mean heat transfer coefficient became maximum near the reattachment point.