In order to study the coupling response process of the liquid tank under the external thermal attack, experiments were carried out on a vertical cylindrical storage tank by electric heating. The response processes of the tank pressure, the medium temperatures, and the wet and dry tank wall temperatures were monitored in the experiments. The coupling responding process between the evolving characters of the medium temperature and the tank wall temperature, as well as the resulting rising features of the tank pressure were analyzed comprehensively. The results indicated that, on the one side the heat transfers process across and through the tank wall were influenced obviously by the thermal-flow fields of the two phase mediums which differ a lot in the thermal physical properties. On the other side, affected by the temperature rise in the wall, the vapor medium became thermal stratified and overheated with respect to the tank pressure, and the flow regime in the liquid medium would transform from causing stratification to promoting de-stratification affected by the wall boiling phenomenon. (C) 2017 Elsevier B.V. All rights reserved.