<p>This study proposes a temperature-dependent sensitivity-index framework for identifying critical members in space frame structures subjected to elevated temperatures. A regular square pyramid space frame is used as a comparative case study, and elastoplastic finite element analyses are carried out in Abaqus using the component-removal approach. For each temperature level, the ultimate load-bearing capacity of the intact structure is compared with that of the damaged structure after removal of a representative member, and a component sensitivity index is calculated from the corresponding capacity reduction. The results show that, within the adopted uniform-temperature idealization, the most sensitive members are consistently located in the central top and bottom chords, whereas peripheral web members remain less sensitive. Temperature mainly changes the magnitude of the sensitivity index rather than its spatial ranking, with the sensitivity index increasing at intermediate temperatures because of thermal-force redistribution and decreasing after severe stiffness degradation and buckling. A comparison among three stiffness levels further shows that lower overall stiffness broadens the range of components exhibiting relatively high sensitivity. The proposed procedure is intended for comparative identification of critical members in regular space frames under globally heated conditions as a limitation and as a improving direction for future work.</p>