Abstract | Large-capacity atmospheric tanks are widely used to store liquids, such as oil or liquefied natural gas. The seismic risk of such industrial facilities is considerably higher compared to ordinary structures, since even some minor damage induced by a ground motion may have uncontrollable consequences, not only on the tank but also on the environment. Recent earthquakes have shown that heavy damage on tanks may lead to temporary loss of essential service, usually followed by leakage and/or fire. Therefore, a Performance-Based Earthquake Engineering (PBEE) framework should be employed for the seismic performance assessment of such critical infrastructure. Current design codes and guidelines have not fully adopted the PBEE concept, while its application to industrial facilities is still at the academic level. This study provides an insight on the seismic risk assessment of liquid storage tanks using a simplified performance-based oriented modelling approach. Appropriate system and component-level damage states are defined by identifying the failure modes that may occur during a strong ground motion. Fragility curves are estimated by introducing both aleatory and epistemic sources of uncertainty, thus providing a comprehensive methodology for the seismic risk assessment of liquid storage tanks.